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851 tools · 26 categories

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All free Toolmoz tools, with a description and a link to open each tool.
Your next little helper	What it does	Open tool
Conversions44 toolsExplore category
2D polar & Cartesian converter	Convert planar coordinates while keeping angle and zero-radius conventions explicit.
Acceleration converter	Convert metres per second squared, standard gravity, feet and Gal.
Amount of substance converter	Convert moles, millimoles, micromoles, nanomoles and picomoles.
Angle converter	Convert angle units with clearly labelled standards.
Angular velocity converter	Translate RPM, revolutions per second, radians and degrees per second.
Area converter	Convert area units with clearly labelled standards.
Capacitance converter	Convert farads, millifarads, microfarads, nanofarads and picofarads.
Data transfer rate converter	Convert data transfer rate units with clearly labelled standards.
Density converter	Convert density units with clearly labelled standards.
Digital storage converter	Convert digital storage units with clearly labelled standards.
Dynamic viscosity converter	Convert centipoise, poise, Pa·s and pound-mass viscosity units.
Electric charge converter	Convert coulombs, amp-hours, milliamp-hours and elementary charges.
Electric current converter	Convert amps, milliamps, microamps and nanoamps.
Electrical conductance converter	Convert siemens, millisiemens, microsiemens and mhos.
Electrical resistance converter	Translate ohms, milliohms, microohms, kilohms and megohms.
Energy converter	Convert energy units with clearly labelled standards.
File transfer time estimate	Estimate a transfer duration from file size, link rate and achieved efficiency.
Force converter	Convert force units with clearly labelled standards.
Frequency converter	Convert frequency units with clearly labelled standards.
Fuel economy converter	Switch between mpg, litres per 100 km and km per litre.
Illuminance converter	Convert lux, footcandles, kilolux, millilux and phot.
Inductance converter	Translate henries, millihenries, microhenries and nanohenries.
Kinematic viscosity converter	Convert centistokes, stokes and square length per second units.
Length converter	Metres, feet, inches and everything in between.
Luminance converter	Convert nits, candela per square metre, footlamberts and stilb.
Magnetic flux converter	Convert webers, milliwebers, microwebers and maxwells.
Magnetic flux density converter	Translate tesla, millitesla, microtesla, nanotesla and gauss.
Mass flow converter	Convert kg/h, g/s, tonnes per hour and pounds per minute.
Molar concentration converter	Convert mol/L, mmol/L, micromoles per litre and mol/m³.
Power converter	Convert power units with clearly labelled standards.
Pressure converter	Convert pressure units with clearly labelled standards.
Specific energy converter	Translate joules per kilogram, watt-hours per kilogram and BTU per pound.
Specific heat capacity converter	Convert J/(kg·K), kJ/(kg·K), calories per gram and BTU heat capacity units.
Speed converter	Convert speed units with clearly labelled standards.
Surface tension converter	Translate N/m, mN/m, dyn/cm and force per length.
Temperature converter	From oven settings to the weather on your next trip.
Thermal conductivity converter	Convert W/(m·K), milliwatts, BTU and calorie thermal conductivity units.
Thermal resistance converter	Convert K/W, degrees Celsius per watt and degrees Fahrenheit per BTU/hour.
Time unit converter	Convert time unit units with clearly labelled standards.
Torque converter	Convert torque units with clearly labelled standards.
Voltage converter	Convert volts, millivolts, microvolts, kilovolts and megavolts.
Volume converter	Convert volume units with clearly labelled standards.
Volumetric flow converter	Convert liquid or gas volume rates, including L/min, CFM and gallons per minute.
Weight converter	Grams to ounces. Kilograms to pounds. A weight off your mind.
Data & CSV58 toolsExplore category
Add CSV row numbers	Add a sequential identifier column without changing the original cells.
Clean CSV cell whitespace	Trim cell edges or collapse internal whitespace without changing headings.
Combine CSV columns	Join selected cells into a new column with your chosen separator.
Combine CSV tables	Append two tables with matching headings or align a union of their columns.
Correlation matrix with heatmap	Compute a Pearson, Spearman or Kendall correlation matrix from CSV columns, with p-values and a colour heatmap.
CSV calculated column	Apply a safe mathematical expression to a numeric column and append the result.
CSV category frequency table	Count exact categories and compare their shares of a selected column.
CSV chart builder	Turn a local CSV into a bar, line or scatter chart with editable columns and SVG export.
CSV column profile	Inspect missing values, distinct values and numeric summaries by column.
CSV crosstab	Cross-tabulate categories with counts, sums or averages.
CSV dataset diff	Compare two keyed datasets and export exact record and cell changes.
CSV date reformatter	Reformat a column of strict ISO dates without locale guessing.
CSV file splitter	Split a table into a ZIP of grouped or fixed-size CSV files.
CSV group and concatenate	Collect text values into one ordered list per group.
CSV grouped summary	Summarise a numeric column separately for each category.
CSV heatmap builder	Explore a numeric matrix as a labelled heatmap, with readable values and SVG export.
CSV identifier padding	Pad textual IDs to a fixed minimum width without losing leading zeros.
CSV lagged change	Compare each numeric value with an earlier row in the current order.
CSV long to wide	Turn identifier/variable/value records into a wider table.
CSV missingness map	Visualise empty-cell patterns and compare completeness across columns.
CSV numeric string cleaner	Remove declared grouping and currency wrappers while preserving decimal digits.
CSV percentage of total	Append each numeric value’s share of its column total.
CSV points to GeoJSON	Build a GeoJSON FeatureCollection from latitude and longitude columns.
CSV rank and percentile	Rank rows with clear tie rules and retain the original record order.
CSV record card maker	Turn table rows into printable cards with a safe local HTML preview.
CSV rule validator	Check required fields and declared column types without uploading records.
CSV running total	Append a cumulative numeric total in the table’s current order.
CSV side-by-side combiner	Combine tables by row position with strict or blank-padded alignment.
CSV split cells into rows	Expand list-valued cells into separate records using a literal separator.
CSV to Excel (XLSX) converter	Turn pasted or uploaded CSV into a real .xlsx workbook: numbers, dates and yes/no values as proper cells, a bold frozen header with filters, sensible column widths and no formula risk.
CSV to JSON	Turn CSV rows into a JSON array of objects.
CSV to SQL INSERT statements	Build quoted INSERT statements while retaining text identifiers and values.
CSV value recoder	Apply an explicit whole-cell value map without substring replacements.
CSV viewer	Open a CSV as a readable table, without uploading it.
CSV wide to long	Turn measurement columns into variable/value rows.
Excel (XLSX) to CSV converter	Turn a sheet (or every sheet) of an Excel .xlsx workbook into CSV, with real dates, your choice of separator and quotes, and a report of formulas, merged cells and hidden sheets.
Extract CSV date parts	Add calendar fields from a strict ISO date column.
Extract unique CSV values	Export one column’s distinct values in first-seen or sorted order.
Fill empty CSV cells	Replace empty values across a table or in one column.
Filter CSV rows	Keep rows matching a literal text or numeric condition.
Find & replace in CSV cells	Replace literal text inside selected cells while keeping the table structure.
Grouped CSV fill down	Carry previous non-empty values forward separately within each group.
Grouped CSV rolling window	Add trailing moving summaries while keeping groups and input order intact.
Join two CSV tables	Match rows across two tables using a shared identifier.
JSON array & NDJSON converter	Convert between an array and one JSON value per line while preserving numeric tokens.
JSON observed-shape summary	Inspect path types and occurrence counts across a nested JSON document.
JSON to CSV	Convert a JSON array of objects into a downloadable CSV.
NDJSON record filter	Filter private line-delimited records using a JSON Pointer and typed equality.
Remove duplicate CSV rows	Keep the first row for each complete record or chosen key.
Rename CSV columns	Apply an explicit heading map while preserving cell contents.
Round a CSV numeric column	Round decimal values with exact half-away-from-zero ties.
Sample CSV rows	Choose a random subset of complete rows without replacement.
Select CSV columns	Keep chosen columns and put them in a different order.
Simple linear regression	Fit a straight line to paired numeric observations.
Sort CSV rows	Sort an export by one column while retaining its header.
Split a CSV column	Separate a cell into several columns using a literal separator.
Text list to CSV	Turn one item per line into a safely quoted single-column CSV.
Transpose CSV	Swap a small CSV’s rows and columns.
Dates & time32 toolsExplore category
12-hour & 24-hour time converter	Translate explicitly written AM/PM times and 24-hour clock times.
Add duration to a clock time	Add or subtract seconds and keep track of midnight crossings.
Add or subtract days	Move a calendar date forwards or backwards.
Add or subtract working days	Move a date using your chosen weekdays and excluded-date list.
Age calculator	Calculate completed calendar years, months and days.
Annual date planner	List the next occurrence of recurring month/day dates after a chosen reference date.
Calendar event file creator	Create a downloadable .ics file for one all-day or UTC-timed event.
Date difference	Count the days between a beginning and a big moment.
Date format converter	Translate explicitly ordered numeric dates into unambiguous formats.
Date range generator	Create a dated list at fixed day intervals, with weekday or weekend filtering.
Date range overlap	Find shared days, combined coverage and the gap between two inclusive date ranges.
Day of the week	Find the weekday, day of the year and ISO week number.
Decimal hours converter	Convert decimal hours to hours:minutes:seconds and back.
Duration adder	Add a list of times, including negative durations.
Easter date calculator	List Western or Orthodox Easter and the related Lent, Holy Week and Pentecost dates for any years.
Elapsed time between dated instants	Compare two ISO date-times with explicit UTC offsets.
Excel date serial converter	Translate date-times and spreadsheet serials while exposing the 1900 leap-day anomaly.
Fiscal year & quarter	Find the year and quarter boundaries for a fiscal year starting in a chosen month.
ISO day-time duration converter	Convert a fixed ISO-style day/time duration to seconds and back.
ISO week date to calendar date	Turn a week-year, ISO week and weekday into a Gregorian calendar date.
Julian date converter	Translate UTC calendar date-times and astronomical Julian dates.
Merge clock-time intervals	Calculate distinct occupied time from overlapping same-day intervals.
Merge date ranges	Combine overlapping inclusive date ranges without double-counting covered days.
Nth weekday of a month	Find the first to fifth, or last, chosen weekday in a month.
Recurring date planner	Generate anchored weekly, monthly or yearly dates with a clear month-end policy.
Shift a list of dates	Move dates by days or calendar months while preserving their input order.
Time duration calculator	Find elapsed time between two clock times.
Time zone viewer	See the same UTC instant in another time zone.
Unix timestamp converter	Convert Unix seconds or milliseconds to a UTC date and back.
Weekday counter	Count Monday–Friday days between two dates.
Work calendar hours	Summarise eligible dates and assumed working hours by month.
Year calendar generator	Make a printable calendar for any year with week numbers and your own marked dates.
Design & colour32 toolsExplore category
2D point transformation	Scale, rotate and translate a point set with a comparison plot and CSV export.
Aspect ratio calculator	Simplify dimensions and resize proportionally.
Barcode generator (EAN-13, UPC-A, Code 128, Code 39)	Make EAN-13, EAN-8, UPC-A, Code 128, Code 39 or ITF barcodes as SVG at a true module width in mm, with check digits and quiet zones.
Bézier curve sampler	Turn control points into an exportable curve and inspect the control polygon.
Camera field of view	Compare sensor dimensions, focal length and approximate scene coverage.
Colour contrast checker	Check text and background contrast against WCAG ratios.
Colour contrast matrix (WCAG 2.2 and APCA)	Check every pair in a palette of up to 16 colours for WCAG 2.2 contrast (AA, AAA, large text) and APCA lightness contrast in one grid.
Colour converter	Convert HEX, RGB and HSL colour values.
Colour space converter (OKLCH, OKLab, Lab, LCH, HWB, Display P3)	Convert any CSS colour to OKLCH, OKLab, Lab, LCH, HWB, Display P3 and XYZ, check the sRGB gamut and see CSS gamut mapping beside clipping.
CSS absolute unit converter	Translate CSS pixels, points, inches and metric absolute units.
CSS gradient generator	Build a two-colour linear gradient and copy the CSS.
Depth of field & hyperfocal	Explore thin-lens focus limits with a chosen blur criterion.
Equivalent shutter exposure	Keep a relative exposure while changing aperture and ISO.
Exposure value calculator	Compare photographic settings on a logarithmic stop scale.
Favicon & ICO generator	Create an ICO and a complete downloadable favicon kit from text or an image.
Flash guide number calculator	Relate ISO, direct-flash distance and aperture using a supplied guide number.
Fluid CSS clamp() generator	Write clamp() values that scale font sizes or spacing smoothly between two viewport widths, for one property or a whole type scale.
Image colour palette extractor	Extract a sampled palette, inspect colour contrast and download reusable swatches.
Image DPI & print size	See the physical print dimensions available at a chosen resolution.
Light distance & falloff	Compare ideal point-source illumination at two distances.
Macro extension estimate	Estimate magnification and exposure allowance from lens extension.
ND filter exposure calculator	Translate filter stops into exposure time, factor and optical density.
Paper grid cutting layout	Compare portrait and rotated grid cuts with margins and gutters.
Pixels & rem converter	Translate CSS pixels and rem using your chosen root size.
Print bleed calculator	Add equal bleed around a trim size and see the artwork dimensions.
Print job quantity & cost	Count printed pages and sheets, allowing for duplex copies.
Print size to pixels	Calculate required pixels for physical artwork dimensions.
Printable graph paper and grid generator	Print true-scale graph paper as PDF or SVG: square, dot, isometric, hexagonal, polar, log, music staff, Cornell or ruled.
QR code generator	Create a downloadable QR code for a link or short text.
QR code reader (read a QR code from a picture)	Read the text inside a QR code from a picture file on your device: a web address, Wi-Fi login, contact, one-time-password key or plain text, and where the code sits in the picture.
Typography scale calculator	Build a modular type scale around a base font size.
Video file size estimator	Estimate a video’s size from duration and combined bitrate.
Developer tools50 toolsExplore category
Base32, Base58, Base62 and Base85 encoder and decoder	Encode text or bytes as Base16, Base32, Crockford, Base58 or Base58Check, Base62, Ascii85 or Z85, and decode them back with exact error positions.
Base64 encoder & decoder	Encode Unicode text to Base64, or decode it back.
Basic Auth header generator	Create an HTTP Basic authorization header locally.
Bitwise calculator	Run AND, OR, XOR, shifts and rotates on fixed-width integers in decimal, hex and binary.
CRC calculator (CRC-8, CRC-16, CRC-32, CRC-64 and custom)	Compute any of the 113 catalogued CRCs, or your own width, polynomial and reflection, of text or hex bytes, with the check value.
Cron expression explainer	Read a five-field cron schedule in plain terms and list its next run times.
HMAC generator	Compute an HMAC-SHA-256, SHA-1, SHA-384 or SHA-512 message authentication code with a secret key, on your device.
HTML editor & live preview	Edit HTML on the left and see your page take shape on the right.
HTML entity encoder & decoder	Escape special characters or decode common HTML entities.
HTTP status code reference	Search every HTTP status code in the IANA registry by number, class or words: meaning, cacheability, retry advice, key headers and the RFC section.
IEEE 754 float bit inspector	See the sign, exponent and fraction bits of a number in half, bfloat16, single, double or quadruple precision, with the exact stored value.
IP range to CIDR converter	Turn a first and last IPv4 address into the smallest list of CIDR blocks.
IPv4 subnet calculator	Find the network, broadcast, host range, mask and address type from a CIDR block.
IPv6 address formatter	Compress, expand and classify an IPv6 address, with an optional prefix range.
JSON flatten & rebuild	Create a reversible typed JSON Pointer manifest and rebuild the original structure.
JSON formatter	Format or minify JSON and catch syntax errors.
JSON Merge Patch	Apply an object merge patch or replace a JSON target with a new value.
JSON Patch applier	Apply a checked sequence of add, remove, replace, move, copy and test operations.
JSON Pointer query	Select a nested value using an exact JSON Pointer, preserving large numeric tokens.
JSON repair and validator for AI output	Fix the JSON a language model gives you: trailing commas, single quotes, comments, code fences, cut-off text and more.
JSON Schema validator	Check a JSON document against a JSON Schema (draft 2020-12 subset) and get a table of every error with its location, plus a list of any keyword that was not checked.
JSON to TypeScript and JSON Schema	Turn sample JSON into TypeScript interfaces and a draft 2020-12 JSON Schema, with optional keys and unions inferred from the samples.
JSON viewer	Explore a collapsible JSON tree, search values, format and minify.
JWT decoder	Inspect a JSON Web Token’s header and payload locally.
JWT signature verifier (HS256, RS256, ES256)	Check a JWT’s signature with an HMAC secret, JWK or PEM public key, and its exp and nbf claims at a time you choose, on your device.
Markdown table generator	Turn CSV into a Markdown, HTML, LaTeX or plain-text table, with alignment.
Markdown table to CSV converter	Turn a Markdown (GitHub style) table, such as one an AI assistant wrote, into CSV for a spreadsheet.
MD5, SHA-1, CRC-32 and Adler-32 generator	Compute classic checksums for text or hex bytes without uploading anything.
Mojibake repair (garbled text fixer)	Repair text like cafÃ© or donâ€™t whose UTF-8 was read as Windows-1252, Latin-1 or MacRoman, including double encoding, with every candidate shown.
Number base converter	Convert whole numbers between bases 2 to 36 exactly.
Password generator	Generate random passwords on your device.
Punycode and IDN domain converter	Convert international domain names to xn-- Punycode and back, compare with the browser’s own conversion and flag lookalike letters.
Regex tester	Test a JavaScript regular expression on your text: every match, its position and capture groups, or a replacement preview.
robots.txt tester	Check which URLs a robots.txt allows or blocks for a crawler, with the exact rule that decided each one, following RFC 9309.
Semantic version compare and range checker	Sort and validate SemVer 2.0.0 versions, test them against npm ranges such as ^1.2.3 or ~1.4 with the reason, and bump them.
SHA hash generator	Create SHA-256, SHA-384 or SHA-512 hashes of text.
Structural JSON diff	Compare nested JSON values by keys and array positions without rounding large identifiers.
Text & binary converter	Encode UTF-8 text as binary bytes and decode it back.
TOML and JSON converter	Convert TOML 1.0.0 to JSON or JSON to TOML, with a typed form that keeps integers, floats and dates exact.
TOTP and HOTP code generator	Work out the RFC 6238 TOTP or RFC 4226 HOTP one-time code for a secret and a time or counter you type, with the otpauth URI.
Unified diff generator	Compare two texts line by line and produce a diff in the format of diff -u and git diff.
Unix chmod calculator	Convert between octal and symbolic Unix permissions, including setuid, setgid and sticky bits.
URL encoder & decoder	Percent-encode a URL component or decode escaped text.
URL parser	Break a URL into its scheme, host, port, path, query parameters and fragment.
UUID and ULID inspector	Decode a UUID of any version or a ULID: version, variant, embedded timestamp in UTC, clock sequence, node and every common spelling.
UUID generator	Generate random version 4 UUIDs.
VLSM subnet planner	Split one network into right-sized subnets for departments, links and VLANs.
X.509 certificate parser and decoder	Read a PEM or DER certificate on your device: subject, issuer, validity, key, extensions, fingerprints and plain factual flags. It does not check trust.
XML formatter and validator	Check that XML is well-formed, then pretty-print or minify it without touching text content.
YAML and JSON converter	Convert YAML to JSON or JSON to YAML, with clear errors and safe handling of anchors.
Education & study12 toolsExplore category
Assignment grade calculator	Combine assignment marks with optional weights and different maximum scores.
Attendance rate planner	See current attendance and how many consecutive attended sessions reach a target.
Classroom group size planner	Split a class into groups with a maximum size or a chosen group count.
Credit-weighted GPA calculator	Calculate a GPA from course credits and grade points you supply.
Custom grade boundary checker	Map a percentage to a grading scale that you define.
Exam score with negative marking	Calculate an exam’s raw and percentage score from its marking scheme.
Flashcard session planner	Estimate a review session from card count, speed and planned breaks.
Reading plan calculator	Turn a page target and daily budget into a manageable reading plan.
Required final exam grade	Find the final-exam percentage needed to reach a target overall grade.
Scale drawing calculator	Convert model or drawing measurements to real dimensions and back.
Study time allocation planner	Divide a study-time budget between subjects using your own priorities.
Video study time calculator	Estimate viewing time at a chosen playback speed with breaks.
Engineering & mechanics25 toolsExplore category
AWG wire gauge calculator	Look up the diameter, area and resistance of an American Wire Gauge size, or find the AWG for a wire diameter.
Beam deflection curves	Plot deflection along a simply supported or cantilever beam for common loading cases.
Belt pulley speeds	Compare pulley RPM and belt speed with a supplied slip allowance.
Bernoulli mechanical head	Separate pressure, velocity and elevation contributions to fluid head.
Circular shaft torsion	Calculate elastic shear stress and twist for solid or hollow circular shafts.
Compound gear train table	Track stage ratios, speed and rotation direction through a compound external gear train.
Conductor skin depth	Estimate field decay depth in a uniform good conductor.
Elastic axial extension	Calculate axial stress, strain and length change of a uniform elastic member.
Elastic bending stress	Calculate outer-fibre normal stress from bending moment and elastic section modulus.
Euler column buckling	Estimate ideal elastic critical load from effective length and section inertia.
Free-space radio path loss	Calculate ideal geometric radio loss from frequency and separation.
Fresnel zone clearance	Find a radio Fresnel-zone radius at a point along a path.
Hydraulic cylinder force & speed	Compare extension and retraction force, speed and stroke time.
Hydraulic fluid & shaft power	Convert pressure difference and volume flow into fluid power and input power.
Hydrostatic force on a vertical rectangle	Find the resultant gauge force and centre-of-pressure depth.
Lead screw motion & torque	Relate screw lead, rotational speed, axial force and efficiency.
Open belt pitch length	Find the geometric belt length and wrap angles between two pulleys.
Pipe Reynolds number	Calculate Reynolds number with explicit density and dynamic viscosity.
Pump affinity scaling	Scale flow, head and power with rotational speed under ideal similarity assumptions.
Rectangle section properties	Find centroidal area moments and elastic section moduli for a rectangular section.
Spur gear pitch geometry	Translate module and tooth count into common involute gear reference diameters.
Three-phase power calculator	Work out kW, kVA and kVAr for a three-phase load, and the capacitor needed to improve its power factor.
Venturi liquid flow estimate	Calculate volume flow from upstream/throat diameters and differential pressure.
Voltage drop calculator	Find the voltage drop, percentage and power lost in a cable run of copper or aluminium.
Wire resistance & temperature	Calculate conductor resistance and apply a supplied linear temperature coefficient.
Everyday & games11 toolsExplore category
Coin flipper	Flip one coin or up to a million, with counts, streaks and how unusual the split is.
Dice roller	Roll multiple dice with your chosen number of sides.
Name wheel spinner	Add names, spin a colourful wheel and reveal a random winner with a little suspense.
Pace calculator	Calculate pace and speed from a distance and finishing time.
Paper size reference	Look up A, B and C series, US Letter, Legal and ANSI paper sizes in millimetres, inches, points and pixels.
Random group generator	Shuffle a list into balanced groups.
Random list picker	Choose items from a list without picking the same line twice.
Secret Santa draw	Draw who gives a gift to whom, with rules to keep couples or housemates from drawing each other.
Stopwatch and countdown timer	A stopwatch with lap and split times and CSV export, plus a countdown timer with quick presets, a finish beep and the time in the tab title, all on your device.
Sudoku solver and checker	Check a Sudoku’s givens, solve it, say whether the solution is unique, rate how hard it is and give a hint without spoiling it.
Trip fuel cost	Estimate fuel quantity and cost from distance and consumption.
Food & cooking25 toolsExplore category
Baker’s percentage calculator	Express every ingredient relative to flour and scale a dough batch.
Baking pan converter	Scale a recipe between round or rectangular baking pans.
Brine percentage calculator	Distinguish salt as a percentage of water from salt as a percentage of final brine.
Chocolate cocoa percentage blend	Mix two labelled cocoa percentages to reach a target batch composition.
Coffee brew ratio calculator	Calculate coffee or brew-water input using a chosen mass ratio.
Coffee extraction comparison log	Compare apparent extraction yield from dose, beverage mass and measured TDS.
Cooking schedule planner	Work backwards from serving time for a sequence of kitchen tasks.
Dehydration mass balance	Estimate final mass from starting and target wet-basis water percentages.
Desired dough water temperature	Apply the empirical temperature-factor worksheet with your mixer friction value.
Dough ball batch planner	Plan a batch weight, handling allowance and ingredient quantities for dough portions.
Fat content substitution	Match the fat mass of one ingredient using another ingredient’s labelled fat percentage.
Ingredient composition table	Express each ingredient as a percentage of the total mix mass.
Ingredient cups & grams converter	Convert ingredient-specific US cups and grams in either direction.
Loaf pan dough loading	Estimate a dough batch from internal pan volume and your chosen loading rate.
Meal prep container allocation	Allocate whole portions into full containers and a remainder container.
Multi-stage starter build budget	Track flour, water and carried starter mass across explicit feeding stages.
Newton cooling & heating curve	Estimate time to a target temperature using a supplied first-order rate constant.
Oven & fan temperature converter	Apply your chosen fan-oven adjustment in Celsius or Fahrenheit.
Pizza party portion planner	Combine group appetites and round the slice budget up to whole pizzas.
Recipe batch scaling table	Scale a complete ingredient table while retaining each stated unit.
Recipe cost calculator	Cost a recipe from pack prices and the quantities you actually use.
Recipe scaler	More guests? Same great recipe. Get every ingredient just right.
Sourdough hydration calculator	Include a starter’s flour and water in your total dough hydration.
Sourdough starter feeding planner	Build a target starter amount with a stated seed:flour:water feeding ratio.
Water mixing temperature	Estimate an equilibrium temperature or hot/cold masses for a target temperature.
Garden & outdoors20 toolsExplore category
Compost carbon–nitrogen mass balance	Combine supplied dry-mass carbon and nitrogen compositions.
Drip irrigation zone budget	Group whole drip lines within a supplied flow capacity.
Fertiliser nutrient mass budget	Sum declared N–P₂O₅–K₂O masses across listed products.
Garden sowing date worksheet	Turn crop offsets into dated sowing and transplant plans.
Gravity tank drain curve	Plot liquid head and outflow as a constant-area tank drains.
Irrigation runtime calculator	Calculate the time needed to deliver a chosen water volume.
Lawn seed quantity calculator	Estimate seed from area and the application rate on your pack.
Liquid orifice discharge	Estimate discharge from head, circular opening size and a supplied coefficient.
Mulch coverage calculator	See how far a bag or delivery will cover at your chosen depth.
Plant pot volume calculator	Estimate a tapered round pot’s internal capacity.
Plant spacing planner	Lay out an evenly spaced rectangular planting grid.
Pond volume calculator	Estimate capacity from surface dimensions and average water depth.
Rainwater collection estimator	Translate rainfall and roof area into a potential collection volume.
Raised bed fill calculator	Account for internal dimensions and unfilled space at the top.
Seed germination batch log	Compare observed germination rates across your seed batches.
Seed tray planner	Estimate trays and seeds for a target number of seedlings.
Soil volume calculator	Estimate loose soil and whole bags for a rectangular area.
Sprinkler catch-can analysis	Calculate catch-depth uniformity and application rate from your measurements.
Square-foot garden grid	Create a labelled planting allocation grid from your chosen cell density.
Succession planting schedule	Plan repeated sowings and expected harvest dates on a calendar.
Health & wellbeing12 toolsExplore category
Alcohol units calculator	Add up UK alcohol units, grams of alcohol and standard drinks for a list of drinks.
Blood glucose converter	Convert blood glucose between mg/dL and mmol/L.
BMI calculator	Calculate adult body mass index using metric or imperial measurements.
BMR calculator	Estimate the energy your body uses at rest with Mifflin–St Jeor.
Cholesterol & triglyceride converter	Convert blood lipid units with the correct factor for each test.
HbA1c converter	Convert HbA1c between NGSP percent and IFCC mmol/mol.
Ideal body weight calculator	Compare Devine, Robinson, Miller and Hamwi weights with the healthy BMI range for your height.
Macro split calculator	Turn a calorie target and percentage split into grams of protein, carbohydrate and fat.
Pregnancy due date calculator	Estimate a due date, gestational age and trimester dates from a last period or conception date.
TDEE calculator	Estimate daily maintenance energy from resting metabolism and activity.
US Navy body fat calculator	Estimate body fat percentage from tape measurements using the US Navy circumference method.
Waist ratio calculator	Work out waist-to-hip and waist-to-height ratios and compare them with WHO and NICE thresholds.
Home & DIY33 toolsExplore category
Appliance electricity cost	Estimate energy and cost from power, usage and your tariff.
Battery energy runtime	Estimate constant-load runtime after supplied usable-depth and efficiency factors.
Battery series/parallel arithmetic	Compare nominal pack voltage, capacity, energy and cell current sharing.
Board feet calculator	Calculate sawn-lumber volume and a price estimate from board dimensions.
Brick quantity estimator	Estimate rectangular wall bricks with mortar joints and openings.
Concrete volume calculator	Estimate concrete volume and bags using the stated bag yield.
Darcy pipe friction loss	Estimate straight-pipe pressure loss using a flow-regime-aware Darcy factor.
Decking board calculator	Estimate whole boards across a rectangular deck.
Electricity bill estimator	Combine meter usage, unit price and a daily standing charge.
Equal mitre angle calculator	Find matching mitre cuts for a flat corner or a regular polygon frame.
Evenly spaced objects	Lay out identical objects with equal edge gaps or fixed end clearances.
Fence post calculator	Count posts and estimate actual equal spacing for a straight fence.
Flooring pack calculator	Work out floor area, whole packs and estimated material cost.
Gravel volume & mass calculator	Estimate loose aggregate volume, mass and whole bags.
Layered wall heat flow	Combine material and surface-film resistances and inspect interface temperatures.
Material cost calculator	Estimate quantities, delivery, tax and a project material total.
Moving box weight allocation	Group listed item units within your chosen box mass budget.
Paint calculator	Estimate wall paint, coverage and cost for a rectangular room.
Paver grid and edge-cut plan	Preview a straight paver grid and export every full or edge-cut position.
Picture hanging layout	Position a centred picture and one or two aligned hanging points.
Pipe fitting minor-loss table	Combine fitting loss coefficients on one velocity basis.
Pipe mean flow velocity	Find mean liquid speed from circular bore diameter and volume flow.
Roof pitch calculator	Translate rise and horizontal run into an angle and rafter length.
Room area planner	Add up multiple rooms and compare square metres with square feet.
Room layout planner	Arrange furniture rectangles on a measured room plan, with snapping, keyboard controls and SVG export.
Shelf carcass panel cut list	List rectangular panels for a simple between-side shelf cabinet.
Slope & gradient calculator	Compare gradient percentage, angle and rise-to-run ratio.
Solar array energy budget	Estimate energy from array rating, equivalent peak-sun hours and supplied derating.
Stair layout calculator	Explore riser count, tread count and straight stair run.
Tile quantity calculator	Estimate tiles and whole boxes from area and tile dimensions.
Two-stroke fuel mix calculator	Work out oil and petrol quantities for a ratio you supply.
Wallpaper calculator	Estimate whole rolls with drop length and pattern-repeat allowances.
Window blind measurement worksheet	Compare three opening measurements and apply a supplied deduction.
Images & photos28 toolsExplore category
Black-and-white dithering	Convert a picture into a one-bit-style dithered PNG.
Crop image	Crop an image using precise pixel coordinates.
Duotone image mapper	Map a photo from a chosen shadow colour to a highlight colour.
Extract image alpha mask	Export the transparency channel as an opaque greyscale PNG.
Flat-colour background cutout	Make pixels near a chosen background colour transparent.
Flip image	Mirror an image horizontally, vertically or both.
Halftone dot image	Turn a picture into a regular grid of ink dots on a chosen paper colour.
Height image to normal map	Build a tangent-style normal texture from a greyscale height interpretation.
Image brightness, contrast and gamma	Adjust a photo with a live preview and an exact exported PNG.
Image canvas padding	Add transparent or coloured space around a picture.
Image comparison slider	Slide between two images or inspect a highlighted pixel-difference map.
Image compressor	Adjust image quality and dimensions, then compare the file size.
Image contact sheet maker	Arrange several pictures into a labelled visual reference sheet.
Image format converter	Convert between PNG, JPEG and WebP on your device.
Image grid tile splitter	Split an image into numbered PNG tiles and download a ZIP.
Image resizer	Resize an image to exact pixel dimensions, with a live preview.
Image RGB and alpha histogram	Inspect full-image channel distributions and export the exact bin counts.
Image threshold mask	Create a binary luminance mask with manual or automatic Otsu thresholding.
Image to pixel-art SVG	Create a compact vector mosaic from a sampled and quantised picture.
Pixelate image	Build a coarse sampled grid and enlarge it into visible pixel blocks.
Rotate image	Turn a photo by 90, 180 or 270 degrees.
Rounded image corners	Clip image corners to a chosen radius and retain transparent edges.
Sobel image edge map	Visualise local image gradients as an opaque greyscale edge map.
Sprite sheet and frame manifest	Pack several images into a fixed-cell PNG atlas with coordinate JSON.
SVG to PNG converter	Turn an SVG drawing, pasted or from a file, into a PNG picture on your device, at a scale or pixel size you choose and with a transparent, white or coloured background.
Text watermark on image	Position a visible text mark with colour, size and opacity controls.
Texture repeat and seam preview	See a 3-by-3 repeat to inspect visible texture edges.
Trim transparent image borders	Crop to the visible alpha bounds and download the trimmed image.
Maths & numbers110 toolsExplore category
2 × 2 eigenvalue calculator	Find real or complex-conjugate eigenvalues of a real 2 × 2 matrix.
3D Euler rotation workspace	Apply an explicit X–Y–Z rotation order and inspect the resulting matrix.
3D line & plane intersection	Intersect an infinite directed line with a plane or identify parallel cases.
3D vector calculator	Calculate lengths, dot and cross products, angle and vector projection.
Adaptive numerical integration	Estimate a definite integral with an evaluation count and error estimate.
Annulus calculator	Find the area, ring width and boundary lengths of a circular ring.
Arc length calculator	Translate a circle’s central angle into an arc length.
Arithmetic sequence calculator	Find a term and partial sum of a constant-step sequence.
Bracketed root finder	Find one root in a sign-changing interval and inspect the final residual.
Capsule volume & area	Measure a cylinder with two hemispherical ends.
Cartesian & spherical coordinates	Translate 3D Cartesian coordinates and radius/azimuth/polar-angle coordinates.
Chinese remainder solver	Solve compatible integer congruences, including non-coprime moduli.
Cholesky decomposition	Factor a small symmetric positive-definite matrix as L times its transpose.
Circle calculator	Find a circle’s area, diameter and circumference from its radius.
Circle intersection points	Find the intersection coordinates of two circles and view their geometry.
Circle through three points	Find the circumcentre, radius and equation of the circle through three plane points.
Circular sector calculator	Calculate a sector’s area, arc and perimeter.
Closest pair in a point cloud	Find the nearest two points and show their distance on a plot.
Combinations & permutations	Count ordered or unordered selections without replacement.
Complex number arithmetic	Add, subtract, multiply or divide complex numbers and inspect polar form.
Cone calculator	Calculate volume, slant height and surface area of a right cone.
Conical frustum calculator	Find the volume and surface areas of a truncated right circular cone.
Continued fractions & convergents	Inspect rational convergents of a supplied decimal number.
Convex hull builder	Find and plot the outer boundary of a point cloud.
Cube calculator	Find a cube’s volume, surface area and space diagonal.
Cuboid calculator	Calculate a rectangular box’s volume, surface and space diagonal.
Cylinder calculator	Find a right cylinder’s volume, curved area and total surface.
Decimal to fraction converter	Convert decimals, repeating decimals and fractions, or find the closest fraction with a small denominator.
Derivative calculator with steps and graph	Differentiate a function symbolically up to the fourth derivative, see each rule applied, and graph f, f′ and the tangent line.
Descriptive statistics	Mean, median, mode, spread and standard deviation for your numbers.
Differential equation solver (Euler, Heun, RK4, adaptive RK45)	Solve y′ = f(x, y) or a system of up to three first-order equations numerically, with step table, error against an exact solution and a plot.
Distance between two points	Find straight-line distance in a two-dimensional coordinate plane.
Ellipse calculator	Calculate area and an approximate ellipse perimeter.
Ellipsoid volume calculator	Calculate volume and axis lengths from three semi-axes.
Exponent calculator	Raise a number to a power with real-number validation.
Factorial calculator	Calculate exact factorials from 0! to 1000!.
Fibonacci and Lucas number calculator	Compute exact Fibonacci or Lucas numbers, list the sequence, or test whether a number belongs to it.
Finite difference table	Build successive forward differences from equally spaced observations.
Fraction calculator	Add, subtract, multiply or divide exact fractions.
Function value table	Sample an expression at evenly spaced X positions and export the full table.
GCD & LCM calculator	Find the greatest common divisor and least common multiple.
Geometric sequence calculator	Find a term and finite sum of a constant-ratio sequence.
Infinite line & circle intersections	Find where the line through two points crosses a circle.
Interactive function plotter	Graph up to three expressions, zoom the viewport and inspect values along the X axis.
Intersection of two planes	Find a point and unit direction for the line where two 3D planes meet.
Iterative linear-system solver	Trace Jacobi or Gauss–Seidel iterations and inspect residual convergence.
Line equation evaluator	Evaluate y = mx + b and find its axis intercepts.
Line segment intersection	Find a crossing point or collinear overlap between two finite segments.
Line slope calculator	Find a line’s gradient and intercept from two points.
Linear equation solver	Solve a single equation of the form ax + b = c.
Linear interpolation calculator	Estimate a y value on the line through two known points.
Linear programming solver (simplex) with graph	Maximise or minimise a linear objective under up to 12 constraints with an exact simplex method, shadow prices and a feasible-region graph.
Logarithm calculator	Calculate a logarithm in a chosen positive base.
Midpoint calculator	Find the point halfway between two coordinate pairs.
Modular multiplicative inverse	Find an exact integer inverse and verify the modular product.
Natural cubic spline workspace	Interpolate an ordered point set with natural endpoint conditions and export samples.
Nth root calculator	Find a real positive- or odd-negative-number root.
Nth roots of a complex number	List and plot all distinct nth roots of a complex value.
Number to words	Write whole numbers in British English.
Numerical derivative workspace	Estimate first and second derivatives and compare sensitivity to the chosen step.
Parallelogram area calculator	Use a base and its perpendicular height to calculate area.
Percentage calculator	Discounts, increases and everyday percentage puzzles.
Percentage change	Find the increase or decrease from one value to another.
Percentage difference	Compare two non-negative values symmetrically.
Percentile calculator	Find an interpolated percentile in a set of numbers.
Pivoted LU decomposition	Inspect lower and upper triangular factors and the row permutation.
Plane through three 3D points	Find a unit-normal plane equation from three non-collinear coordinates.
Point-in-polygon checker	Test whether a point lies inside, outside or on the edge of a polygon.
Point-to-plane distance	Find signed distance and the closest point on a 3D plane.
Polygon centroid calculator	Locate the uniform-area centre of a simple polygon and plot it.
Polygon coordinate area	Calculate a simple polygon’s area from ordered coordinates.
Polynomial arithmetic	Add, subtract or multiply polynomial coefficient lists and export the resulting coefficients.
Polynomial evaluator	Evaluate a coefficient list and its derivative using Horner arithmetic.
Polynomial interpolation workspace	Interpolate up to 20 points and export a sampled polynomial curve.
Polynomial least-squares fit	Fit a low-degree curve to point data and inspect fitted values and residuals.
Polynomial long division	Divide two polynomial coefficient lists and inspect quotient and remainder.
Prime factorisation	Break a whole number into its prime factors.
Prime number checker	Check whether a whole number is prime.
Proportion calculator	Solve a / b = c / x for the missing fourth value.
Pythagorean calculator	Find the hypotenuse of a right-angled triangle.
QR decomposition	Factor a small matrix into an orthonormal basis and upper-triangular coefficients.
Quadratic equation solver	Solve ax² + bx + c = 0, including complex roots.
Quaternion vector rotation	Normalise a Hamilton quaternion and use it to rotate a 3D vector.
Random number generator	Generate unbiased whole numbers within your chosen range.
Ratio simplifier	Reduce a ratio of whole numbers to its simplest form.
Rectangle calculator	Calculate area, perimeter and diagonal from two side lengths.
Rectangular pyramid calculator	Calculate a centred right pyramid’s volume, side areas and edge length.
Regular polygon calculator	Find the area, perimeter and radii of a regular polygon.
Right triangle solver	Solve a right triangle from any two known sides, or a side and an acute angle.
Roman numeral converter	Convert whole numbers and canonical Roman numerals.
Row reduction, rank & nullspace	Reduce a small matrix and inspect pivot columns, numerical rank and nullspace basis.
Scientific expression calculator	Evaluate several lines of arithmetic with functions, variables and the previous answer.
Scientific notation converter	Express a number in standard and scientific notation.
Set operations calculator	Find the union, intersection, differences and Cartesian product of two sets, with Jaccard similarity.
Significant figures calculator	Count significant figures, or round a number to a set number of significant figures or decimal places.
Small matrix calculator	Add, multiply, transpose, invert or find a determinant for matrices up to 6 × 6.
Sphere calculator	Calculate a sphere’s volume and surface area from its radius.
Spherical cap calculator	Calculate the volume, base radius and surface areas of a sphere cut by a plane.
Standard error of the mean	Summarise sample variability and the standard error of its mean.
Taylor and Maclaurin series calculator	Find the Taylor or Maclaurin polynomial of a function to order 20, with exact coefficients, an error estimate and a graph.
Trapezoid area calculator	Find area from parallel sides and perpendicular height.
Triangle barycentric coordinates	Express a point as weights of three triangle vertices and check containment.
Triangle calculator	Find area and perimeter from three side lengths.
Triangle centres from coordinates	Plot the centroid, incentre, circumcentre, orthocentre and nine-point centre.
Triangle from sides & angles	Solve a plane triangle from two sides and their included angle, or one side and two angles.
Truth table generator	Build a truth table for a logical expression and see its minterms and normal forms.
Two linear equations solver	Solve two equations in x and y using their coefficients.
Venn diagram builder	Compare two or three lists, see exact overlaps and export the diagram and memberships.
Weighted average	Calculate an average with a different weight for each value.
Z-score calculator	Express a value in standard deviations from a supplied mean.
Money & shopping65 toolsExplore category
Advertising campaign calculator	Calculate CPC, CPM, conversion rate, CPA and ROAS together.
Bill splitter	Good company. Fair shares. Split the bill, tip included.
Bond price and yield to maturity calculator	Find a bond’s price from its yield, or its yield from its price, with duration and convexity.
Break-even calculator	Estimate units needed to cover fixed and variable costs.
Cash runway calculator	Compare available cash with a constant monthly operating cash burn.
Compound annual growth rate	Find the constant annual growth rate between two positive values.
Compound interest calculator	Explore a savings balance with regular contributions and compounding.
Currency converter	Convert currencies with dated daily exchange rates, without fees or signups.
Customer acquisition cost	Compare acquisition expenditure with new customers over the same period.
Customer retention rate	Calculate retained customers after removing newly acquired customers.
Customer value scenario	Estimate gross customer profit from order value, frequency and lifetime.
Doubling time calculator	Find how long growth takes to double (or triple), and compare the exact answer with the rule of 72.
Economic order quantity	Explore the basic constant-demand inventory order model.
Effective annual rate calculator	Compare a nominal annual rate with its compounded annual equivalent.
Equal instalment plan	Split a remaining amount into cent-exact payments with due dates.
Fixed payment debt payoff	Estimate a payoff schedule from a balance, interest rate and monthly payment.
Freelance hourly rate planner	Translate an annual revenue requirement into billable hours and a rate.
Gross salary equivalent	Translate annual gross pay into monthly, weekly, daily and hourly equivalents.
IBAN validator and check digit calculator	Check an IBAN against the SWIFT registry: length, character types, mod 97 check digits and its bank and branch parts. Or calculate check digits for a BBAN.
Inflation & purchasing power	Explore future prices and the present purchasing power of an amount.
Inflation-adjusted return	Compare an effective return with inflation over the same period.
Inventory turnover calculator	Compare cost of goods sold with average inventory over one period.
Invoice line-item calculator	Total quantities and unit prices with a supplied discount, delivery and tax.
IRR calculator	Find the internal rate of return of evenly spaced cash flows, including multiple-rate cases.
LLM API cost calculator	Work out what a prompt and answer cost per request, per month and per year from the prices you enter.
Loan APR calculator	Work out the APR of a loan including upfront and monthly fees, in both UK/EU and US conventions.
Loan overpayment calculator	Compare an additional monthly payment with a fixed-rate repayment schedule.
Loan repayment calculator	Estimate fixed monthly payments and download an amortisation schedule.
Margin & markup calculator	Distinguish gross margin from markup on cost.
Marketplace fee & price calculator	See net proceeds or find a price for your target profit after fees.
Meeting cost calculator	Estimate the value of attendee time using your own hourly rates.
Mortgage calculator with overpayments and chart	Mortgage payment, total interest and payoff time with overpayments, a fixed rate then a reversion rate, a chart and a downloadable monthly schedule.
Multiple discount calculator	Apply successive discounts and see the effective overall saving.
Net present value calculator	Discount a series of end-of-period cash flows and subtract the initial cost.
Overtime pay calculator	Calculate gross pay with a threshold and overtime multiplier you choose.
Parcel dimensional weight	Compare actual and volumetric weight using your carrier’s divisor.
Present value of regular payments	Discount a fixed series of equal end-of-period payments.
Reorder point calculator	Combine expected demand during lead time with a supplied safety stock.
Retirement pot and drawdown projection	Project a retirement pot from contributions, returns, charges and inflation, then see how long an income lasts, with a chart, yearly table and lower-returns check.
Return on investment calculator	Compare final proceeds with the complete cost you supply.
Sales funnel calculator	Compare stage counts and see step and overall conversion rates.
Savings goal calculator	Work out a monthly contribution or time to reach a savings target.
Savings withdrawal scenario	See how a constant monthly withdrawal changes a starting balance.
Shared expense settlement	Balance an equal-share expense pool and show suggested transfers.
Simple interest calculator	Estimate interest without compounding or additional payments.
Simple payback period	Estimate when non-negative periodic cash inflows recover an initial outlay.
Stock average cost calculator	Combine share purchases into an average cost, break-even price and gain or loss.
Straight-line depreciation	Spread depreciable cost over a supplied useful life.
Subscription cost calculator	Compare recurring charges on monthly and annual bases.
Tiered sales commission	Apply progressive commission rates to successive sales bands.
Timesheet hours calculator	Add work intervals and unpaid breaks from a local CSV.
TVM calculator (time value of money)	Solve for any one of the number of payments, interest rate, present value, payment or future value, with payment timing, compounding, a balance chart and a downloadable schedule.
UK Capital Gains Tax calculator	Work out UK Capital Gains Tax on gains from shares, property and other assets using dated GOV.UK and HMRC rates and the tax-free allowance for 2026/27 and 2025/26.
UK dividend tax calculator	Work out the Income Tax on UK dividends alongside your other income, with the dividend allowance and dated GOV.UK and HMRC rates for 2026/27 and 2025/26.
UK High Income Child Benefit Charge calculator	Estimate the UK High Income Child Benefit Charge from your adjusted net income and the number of children, using dated GOV.UK and HMRC figures for 2026/27 and 2025/26.
UK pension annual allowance calculator (with tapering)	Check your UK pension annual allowance and whether high income tapers it, from threshold income and adjusted income, using dated GOV.UK and HMRC limits for 2026/27 and 2025/26.
UK self-employed National Insurance calculator	Work out Class 4 and Class 2 National Insurance on self-employed profits using dated GOV.UK and HMRC thresholds and rates for 2026/27 and 2025/26.
UK stamp duty calculator (SDLT, LBTT, LTT)	Work out stamp duty for a UK property purchase in England, Northern Ireland, Scotland or Wales from the rates in force on the transaction date, with sources and a review date.
UK student loan repayment calculator	Work out what you repay on a UK student loan (Plans 1, 2, 4 and 5 and the Postgraduate Loan) from your pay, using dated GOV.UK and HMRC thresholds for 2026/27 and 2025/26.
UK take-home pay calculator	Estimate UK take-home pay after income tax, National Insurance, student loan and pension, using dated GOV.UK and HMRC rates for 2026/27 and 2025/26.
UK VAT registration check	Check whether your taxable turnover has passed the UK VAT registration limit, by when to apply and your registration date, using dated GOV.UK and HMRC limits.
Unit price calculator	Compare two pack sizes on the same unit basis.
VAT add & remove calculator	Add a supplied VAT rate or extract it from a gross price.
Working capital calculator	Calculate net working capital and the current ratio.
XIRR calculator for dated cash flows	Find the annual return of irregularly dated payments, using the same convention as Excel.
Music & audio24 toolsExplore category
Add independent sound levels	Combine uncorrelated sound levels measured using the same reference.
Audio file size estimator	Estimate uncompressed PCM size or fixed-bitrate encoded audio size.
Audio samples & time	Translate sample-frame counts and durations at a chosen sample rate.
Axial room mode calculator	Explore ideal axial resonances along a rectangular room’s three dimensions.
Bars, beats & duration	Convert bars to elapsed time or elapsed time into bars and beats.
Chord note calculator	Find the notes and frequencies of common root-position chords.
Decibels & linear ratio	Convert gain in dB to a linear amplitude or power ratio, and back.
Frequency to musical note	Find the nearest equal-tempered note and its tuning offset.
Guitar fretboard note finder	List the notes across frets for your own open-string tuning.
Ideal string tension calculator	Estimate tension from vibrating length, frequency and linear density.
Instrument fret position calculator	Calculate equal-tempered fret positions along a supplied scale length.
Loudness gain & peak headroom	Estimate a gain-only loudness adjustment against a supplied true-peak ceiling.
Metronome with tap tempo	A free online metronome from 20 to 300 BPM with time signatures, subdivisions, accent patterns, tap tempo and a numbered beat display, timed on the audio clock.
Musical interval calculator	Compare two notes in semitones, octaves and frequency ratio.
Musical note frequency	Find a note’s frequency and MIDI number with adjustable concert pitch.
Musical scale builder	Build a scale with correctly ordered note-letter spellings.
Note list transposer	Move a list of octave-labelled notes by a chosen number of semitones.
Polyrhythm timing grid	See where two equal subdivisions meet across one practice cycle.
Sample-rate playback change	See the pitch and duration effect of reinterpreting a recording’s sample rate.
Speaker distance delay	Translate a path-length difference into an acoustic alignment delay.
Swing timing calculator	Split a pair of eighth notes into a chosen long-short timing ratio.
Tempo & delay time calculator	Get straight, dotted and triplet note lengths for a quarter-note BPM.
Tempo speed-change calculator	Compare tempo, duration and pitch when playback speed changes.
WAV waveform & trimmer	Inspect a waveform, choose a region, preview it and download a trimmed WAV locally.
Outdoors & maps14 toolsExplore category
Coordinate from distance & bearing	Find a spherical destination from a starting point and initial bearing.
Coordinate route distance	Add spherical leg distances along an ordered list of coordinates.
GeoJSON points to CSV	Extract Point and MultiPoint coordinates into an ordinary downloadable table.
GeoJSON structure inspector	Inspect geometry counts, position ranges and common structural errors locally.
Geometric horizon distance	Estimate an unobstructed horizon from height above a spherical surface.
Great-circle distance & bearing	Compare two coordinates using a spherical Earth model.
Latitude & longitude format	Translate signed decimal coordinates and degrees, minutes and seconds.
Latitude–longitude rectangle area	Estimate the spherical surface area inside geographic bounds.
Manning open-channel flow	Estimate uniform flow in a rectangular or trapezoidal channel.
Moon phase calculator	Show the Moon’s phase, illumination and age for a date, with the next new, quarter and full moons.
Open-channel Froude number	Compare flow speed with the shallow-water gravity-wave scale.
Sunrise and sunset calculator	Find sunrise, sunset, solar noon, day length and twilight for any latitude, longitude and date.
Walking & ascent time planner	Combine your walking pace, ascent allowance and planned breaks.
Web Mercator coordinate converter	Convert decimal coordinates to or from EPSG:3857 map metres.
PDF & files22 toolsExplore category
Add a drawn signature to a PDF	Draw or upload your signature and place it on a PDF page, with an optional caption.
Add PDF page numbers	Add sequential footer numbers to all or selected PDF pages.
Backup storage estimate	Combine retained full and incremental payloads with supplied storage allowances.
Crop PDF pages	Trim the margins of some or all PDF pages by a set number of millimetres.
Extract PDF pages	Keep selected pages or ranges in a new PDF.
File hash calculator and verifier	Work out the MD5, SHA-1, SHA-256, SHA-384, SHA-512 or CRC-32 of files or text, and check them against a published checksum.
File type detector (magic bytes)	Find out what a file really is from its first bytes: PNG, JPEG, PDF, ZIP, Office, executables and more than a hundred other formats, and whether its name agrees.
Fill in a PDF form	Type into the fields of a PDF form, tick boxes and pick options, then save a filled copy or a flattened one.
Hex dump viewer	Look at the bytes of a file or pasted data as an xxd-style hex dump, search for text or hex, jump to a match and read numbers at any offset.
Images to PDF	Arrange PNG, JPEG or WebP images into one PDF on your device.
Merge PDFs	Combine PDF files in the order you choose, entirely on your device.
PDF text extractor	Pull the text out of a PDF page by page on your device, with page markers, a count for each page and a plain warning when a page is a scan with no text to extract.
PDF to images (PNG or JPEG)	Turn PDF pages into PNG or JPEG pictures at a resolution you choose, in a ZIP.
Photo and PDF metadata viewer	See the hidden data in a JPEG, PNG, WebP or PDF: camera and phone, date, GPS location, author and software.
Redact a PDF (remove text for good)	Cover names, numbers and other private details in a PDF so they are removed from the file, not just hidden under a black box.
Remove EXIF and metadata from photos and PDFs	Strip location, camera, author and other hidden data from JPEG, PNG, WebP and PDF files without changing image quality.
Reorder PDF pages	Put every PDF page into the exact order you choose.
Rotate PDF pages	Rotate all or selected pages in a PDF.
Split PDF into pages	Download each PDF page as a separate file in one ZIP.
Text file inspector (encoding, line endings, hidden characters)	Check a text or CSV file for its encoding, byte order mark, line endings, mixed tabs and spaces, trailing spaces and invisible Unicode characters, and download a cleaned copy.
Watermark PDF	Add a translucent text watermark to all or selected PDF pages.
ZIP archive inspector	Browse a ZIP, search its files and extract individual entries without uploading the archive.
Planning & productivity18 toolsExplore category
Critical path method (CPM) and PERT calculator	Find the critical path, float and project duration from tasks and predecessors, or add PERT estimates for the chance of finishing on time, with a Gantt chart.
Deadline status board	Sort a dated task table by days remaining relative to your reference date.
Erlang B and Erlang C calculator (call centre staffing)	Erlang C and Erlang B calculator: agents needed for a service level such as 80/20, lines for a blocking target, shrinkage, a table and a chart.
Focus & break session planner	Plan focus sessions with short breaks and an occasional longer break.
Household chore rotation	Create a weekly task worksheet with a predictable person rotation.
Knockout bracket worksheet	Build a single-elimination match path with first-round byes.
Meeting availability overlap	Find shared time windows from several people’s same-day availability.
Packing weight manifest	Sum item quantities and compare the contents mass of each named bag.
Parallel task schedule planner	Schedule independent jobs across equal lanes and visualise elapsed time.
Party seating allocation	Keep parties together while filling tables with a simple transparent heuristic.
Project timeline & Gantt chart	Turn dated tasks into an editable timeline with progress bars and SVG export.
Rectangular box fit calculator	Compare uniform grid orientations of smaller boxes inside a larger box.
Round-robin fixture maker	Generate every pair once, with automatic byes for odd participant counts.
Staff coverage lower bound	Compare required coverage hours with productive hours per person.
Volunteer role rotation	Create repeatable round-by-round role assignments from your own participant list.
Weekly time budget	Add recurring activities and compare them with a 168-hour week.
Weighted decision matrix	Compare options using your own criteria, directions and weights, with an exportable ranking.
Work capacity planner	Translate a backlog and your working-time assumptions into throughput.
Science & engineering72 toolsExplore category
555 astable timer calculator	Estimate standard 555 timing, frequency and high-state duty cycle.
Acid-base titration curve calculator	Plot pH against titrant volume for strong or weak, mono- or polyprotic acids and bases from the exact charge balance, with equivalence points and an indicator.
Arrhenius rate ratio	Compare rate constants at two absolute temperatures using an activation energy.
Average acceleration calculator	Find velocity change per unit time.
Boiling & freezing point shifts	Estimate ideal boiling-point elevation and freezing-point depression from molality.
Buoyant force calculator	Find ideal buoyancy from displaced fluid volume and density.
Capacitive & inductive reactance	Find ideal reactance magnitudes and signed imaginary impedance at a frequency.
Capacitor charge sharing	Calculate the ideal final voltage when two charged capacitors are connected in parallel.
Capacitor energy calculator	Find stored charge and energy from capacitance and voltage.
Centripetal force calculator	Find the inward force required for uniform circular motion.
Charge from current & time	Translate a constant current and duration into electric charge.
Chemical equation balancer	Balance a chemical equation with the smallest whole-number coefficients, including ions.
Constant acceleration calculator	Find velocity and displacement in a one-dimensional motion model.
Coplanar Hohmann transfer	Compare ideal tangential impulses and coast time between two circular orbits.
DC electrical power calculator	Relate voltage and current to power and energy over time.
Doppler effect calculator	Find the frequency an observer hears or sees when the source or observer moves, for sound and for light.
Empirical formula calculator	Find the simplest whole-number formula from percentage composition or masses, and the molecular formula from a molar mass.
Energy efficiency calculator	Compare useful energy output with total energy input.
First-order RC filter	Find the ideal cutoff, gain and phase of an unloaded RC low-pass or high-pass filter.
Frequency & period calculator	Convert frequency into cycle period, or period into frequency.
Gravitational potential energy	Calculate a near-surface energy change from a vertical height change.
Greybody radiative heat exchange	Compare emitted power and net exchange with a large surrounding environment.
Half-life and decay calculator	Solve for remaining amount, elapsed time or half-life in exponential decay.
Hooke’s law calculator	Find the restoring force for an ideal linear spring.
Ideal circular orbit	Calculate circular speed, period and local escape speed around a supplied central mass.
Ideal gas density calculator	Calculate mass density from absolute pressure, temperature and molar mass.
Ideal gas pressure calculator	Estimate absolute pressure from gas amount, volume and temperature.
Ideal op-amp gain	Compare ideal inverting and non-inverting closed-loop amplifier results.
Ideal osmotic pressure	Estimate dilute-solution osmotic pressure from concentration and a particle factor.
Ideal projectile motion	Explore range, height and flight time for a level-ground model.
Ideal rocket delta-v	Relate mass ratio and specific impulse to ideal velocity change.
Ideal transformer ratios	Relate winding turns, RMS voltages, currents and reflected resistance.
Interactive pendulum simulation	Change a pendulum’s length, gravity and damping, then watch its motion and angle trace.
Kinetic energy calculator	Find classical kinetic energy from mass and speed.
LC resonance calculator	Calculate an ideal LC resonant frequency and the series-RLC quality factor.
LED series resistor calculator	Estimate the ideal resistor and dissipation for a low-voltage DC LED string.
Limiting reagent and theoretical yield calculator	Balance a reaction, find the limiting reagent from masses or moles, and get the theoretical yield, leftover reactants and percent yield.
Linear thermal expansion	Estimate a length change using a supplied expansion coefficient.
Loaded voltage divider	Calculate a resistor divider with an optional load across its lower resistor.
Mass & moles calculator	Convert a mass and molar mass into amount of substance, or back.
Molality calculator	Calculate solute moles per kilogram of solvent, keeping solvent and solution mass separate.
Molar mass calculator	Find the molar mass, element-by-element composition and moles of a chemical formula.
Molarity calculator	Calculate concentration from solute amount and final solution volume.
Momentum calculator	Calculate one-dimensional classical momentum.
Newton’s second law calculator	Relate mass and acceleration to net force.
Ohm’s law calculator	Calculate current and resistor power from voltage and resistance.
Periodic table element lookup	Find an element by name, symbol or atomic number, with its weight, group, block and electron configuration.
pH, pOH & concentration	Relate pH, pOH and idealised hydronium/hydroxide concentrations using a stated pKw.
Photon energy and wavelength calculator	Convert between wavelength, frequency and photon energy in eV and joules.
Pressure from force & area	Calculate average normal pressure on a surface.
RC time constant calculator	Estimate ideal resistor-capacitor charging and discharging.
Reaction percentage yield	Compare actual product yield with a supplied theoretical yield.
Resistor colour code reader	Decode four- or five-band resistor values and tolerance limits.
Resistor tolerance checker	Compare a set of measured resistances against a nominal value and tolerance.
RL current rise calculator	Explore an ideal series RL step response and stored magnetic energy.
Serial dilution planner	Build a concentration table for equal-volume repeated dilution steps.
Series & parallel capacitors	Calculate ideal capacitance in series or parallel.
Series & parallel resistors	Calculate ideal resistance in series or parallel.
Series RLC impedance	Calculate impedance, RMS current, phase and real power for an ideal series RLC circuit.
Simple pendulum period	Estimate a small-angle pendulum’s period and frequency.
Snell’s law refraction calculator	Find the refraction angle, critical angle, Brewster angle and reflectance at an interface.
Solution concentration by blending	Mix two solutions of the same solute using mass percentages.
Solution dilution calculator	Calculate stock volume for a target concentration and final volume.
Specific heat energy calculator	Estimate energy for a temperature change without a phase transition.
Spring energy calculator	Calculate elastic potential energy stored in an ideal spring.
Stokes settling velocity	Estimate a small sphere’s settling speed and inspect the resulting Reynolds number.
Thin lens equation calculator	Solve for image distance, object distance or focal length, with magnification, image type and lens power.
Two-branch current divider	Split a supplied total current between two ideal parallel resistors.
Wave speed calculator	Relate wavelength and frequency to wave speed.
Waveform RMS & peak	Compare peak, peak-to-peak and RMS for ideal symmetric periodic waveforms.
Weak acid buffer pH	Explore the Henderson–Hasselbalch model with a stated conjugate pair.
Work by a constant force	Calculate work from force, displacement and their angle.
Sewing & crafts20 toolsExplore category
Bead string length planner	Fit whole beads and spacers into a target necklace or bracelet length.
Bias binding fabric area	Estimate the fabric area behind a chosen length and cut width of bias strip.
Circle skirt dimensions	Calculate waist and hem radii for full, half and quarter circle skirt sectors.
Crochet circle round counts	Build a round-by-round stitch-count reference for constant increases.
Cross-stitch fabric size	Preview the stitched rectangle and fabric margins from count and stitch dimensions.
Curtain fabric planner	Estimate joined fabric widths, repeat-matched drops and total fabric length.
Embroidery thread budget	Estimate skein quantity from measured stitch use and working strands.
Fabric shrinkage calculator	Measure shrinkage in each direction and allow for it before cutting.
Half-square triangle cut planner	Plan two-at-a-time HST starting squares with explicit trimming allowance.
Knitting & crochet gauge planner	Turn a measured swatch into stitch and row counts, including repeat multiples.
Knitting shaping row planner	Distribute one-stitch increases or decreases across a row schedule.
Macramé cord cutting budget	Turn a measured knot multiplier into cut lengths and spool counts.
Patchwork strip cutting yield	Estimate fabric length and spare pieces from repeated rectangular strip cuts.
Picture frame mat layout	Preview an artwork opening with centred or bottom-weighted borders.
Quilt binding calculator	Plan straight-grain binding strips and fabric yardage from a quilt perimeter.
Quilt block layout planner	Preview a square-block quilt and calculate finished and cut dimensions.
Resin casting material budget	Estimate mixed volume and component masses from supplied product data.
Weaving sett and reed planner	Compare target warp ends with a fixed reed denting arrangement.
Weaving warp length budget	Budget warp per end and total yarn for repeated woven pieces.
Yarn quantity substitution	Match a pattern’s total yarn length to a replacement skein size.
Sport & fitness11 toolsExplore category
Calories burned (MET) calculator	Estimate the energy used by an activity from its MET value, your weight and the time spent.
Elo rating change model	Explore expected scores and updates with your own scale and K factor.
Even-pace race split planner	Break a target distance and finish time into equal-pace splits.
Heart rate zone calculator	Work out five training zones from your age, resting rate and a maximum heart rate formula.
Interval session planner	Add work, recovery, warm-up and cooldown blocks into a session plan.
League table calculator	Build standings from match scores and points rules you provide.
One-rep max calculator	Estimate your one-repetition maximum from a set with six published formulas.
Race time predictor	Predict finish times from one recent race using Riegel’s formula, with pace per kilometre and mile.
Round-robin tournament schedule	Create match rounds and court/time slots without double-booking a team.
Seeded knockout bracket	Lay out a single-elimination bracket with explicit first-round byes.
VO2 max estimator	Estimate aerobic fitness from a Cooper 12-minute run or from your maximum and resting heart rates.
Statistics & probability62 toolsExplore category
2×2 table: risk ratio, odds ratio and Fisher exact test	Analyse a 2×2 table of exposure and outcome counts with risk ratio, odds ratio and exact p-values.
A/B test sample size calculator	Estimate how many visitors each variant needs to detect a chosen change in conversion rate.
A/B test significance calculator	Test whether the difference between two conversion rates is statistically significant.
Bayes probability calculator	Update an event probability using evidence rates you supply.
Binomial probability calculator	Find exact and cumulative success probabilities for independent trials.
Box plot builder	Compare grouped distributions, medians, spread and outliers from your own CSV.
Chi-square goodness of fit	Compare observed category counts with expected relative weights.
Coefficient of variation	Compare sample spread with its positive mean on a ratio scale.
Cohen’s kappa calculator	Measure agreement between two raters beyond chance, with optional weights for ordered categories.
Confidence interval for a mean	Estimate a mean interval using a sample and Student’s t distribution.
Contingency table chi-square test	Compare two categorical variables using an observed count table.
Cronbach’s alpha (scale reliability)	Measure the internal consistency of questionnaire items with Cronbach’s alpha, alpha if an item is deleted, item-total correlations and a Feldt interval.
Diagnostic test calculator (sensitivity, specificity, predictive values)	Work out sensitivity, specificity, predictive values, likelihood ratios and more from a 2×2 table, each with a confidence interval.
Discrete expected value	Calculate an outcome distribution’s mean, variance and standard deviation.
Exponential waiting time	Estimate a waiting-time probability under a constant-rate model.
Fleiss’ kappa calculator (agreement among three or more raters)	Measure agreement beyond chance among several raters who each sort the same subjects into categories: Fleiss’ kappa, per-category kappa, a z test and Landis and Koch labels.
Geometric mean calculator	Average positive multiplicative values using logarithms.
Grubbs outlier test calculator	Check one list of numbers for a single outlier with Grubbs’ test: the G statistic, critical value, p-value, the flagged value and its position, two-sided or one-sided.
Harmonic mean calculator	Average positive rates with an equal numerator basis.
Histogram frequency table	Bin a numeric list into equal-width intervals with cumulative counts.
Independent-samples effect size	Compare two sample means in pooled standard-deviation units.
Interquartile outlier finder	List values outside configurable interquartile-range fences.
Intraclass correlation (ICC) calculator, all six Shrout and Fleiss forms	Work out the intraclass correlation from a subjects by raters table: all six Shrout and Fleiss forms with ANOVA mean squares, F tests, confidence intervals and a plot.
Kaplan-Meier survival curve	Plot Kaplan-Meier survival curves from times and event codes, with Greenwood intervals, median survival and a log-rank test between groups.
Kruskal-Wallis test calculator with Dunn post-hoc comparisons	Compare three or more groups without assuming normality using the Kruskal-Wallis test: tie-corrected H, p-value, epsilon-squared effect size and Dunn pairwise comparisons.
Mann–Whitney U test calculator	Compare two independent groups without assuming a normal distribution, with exact p-values for small samples.
McNemar test calculator for paired proportions	Test whether a paired yes/no result changed from a 2×2 table of matched outcomes: exact, mid-p and chi-square McNemar p-values, the discordant odds ratio and an interval for the difference.
Median absolute deviation	Summarise spread using deviations from the sample median.
Meta-analysis forest plot	Pool studies with fixed-effect and random-effects meta-analysis and draw a forest plot with heterogeneity, I² and a prediction interval.
Min–max normalisation	Rescale a numeric dataset into a chosen output interval.
Moving average calculator	Smooth an ordered numeric series with a complete trailing window.
Multiple comparisons p-value correction	Adjust several p-values with Bonferroni, Holm or Benjamini–Hochberg corrections.
Multiple linear regression calculator	Fit a linear regression with one or more predictors from a pasted table: coefficients, standard errors, p-values, R², the F test and a fit plot.
Net Promoter Score calculator	Calculate NPS and its margin of error from response counts or raw 0–10 scores.
Normal interval probability	Find the probability inside and outside an interval under a normal model.
Normal percentile value	Find the value below which a chosen share of a normal distribution lies.
Normal Q-Q plot and normality tests	Draw a normal Q-Q plot of your numbers and check them with the Jarque-Bera, D’Agostino-Pearson and Anderson-Darling tests.
Number needed to treat (NNT) calculator with confidence interval	Work out the number needed to treat from event counts or rates: absolute and relative risk reduction, odds ratio and an NNT interval that stays correct when it includes no effect.
One-sample t test	Compare a numeric sample mean with a supplied reference value.
One-way ANOVA calculator	Compare the means of two or more groups with an F test and an ANOVA table.
P-value and critical value calculator	Convert a z, t, chi-square or F statistic into an exact p-value and critical value.
Paired sample t test	Compare matched observations by analysing their within-pair differences.
Pearson correlation test	Test and measure the straight-line relationship between two variables, with a confidence interval and regression line.
Poisson probability calculator	Explore event-count probabilities for a supplied average rate.
Prediction error calculator	Compare matched actual and predicted values with common error measures.
Probability & odds converter	Translate an event probability into mathematical odds for and against.
ROC curve and AUC calculator	Draw a ROC curve from scores and true labels, with the AUC, its DeLong confidence interval and the best cut-off by Youden’s J.
Root mean square calculator	Calculate the quadratic magnitude of positive and negative values.
Sample size and power for a t test	Find the sample size, power or smallest detectable effect for a one-sample, paired or two-sample t test, from the exact non-central t distribution.
Sampling without replacement	Find success-count probabilities when drawing from a finite population.
Shared birthday probability	Explore the chance of a matching category in a group.
Spearman rank correlation	Measure the association between two paired lists using ranks.
Standardise a numeric dataset	Convert each observation into a dataset-based standard score.
Survey sample size estimate	Plan a sample for a proportion using a supplied margin of error.
Trials until first success	Find the chance that the first success occurs on a particular trial.
Trimmed mean calculator	Average a dataset after removing a chosen share from each end.
Two-event probability calculator	Work out union, neither and conditional probabilities from an intersection.
Uniform interval probability	Compare an interval with a continuous uniform distribution’s support.
Weighted median calculator	Find the first ordered value reaching half the total weight.
Welch two-sample t test	Compare independent sample means without assuming equal variances.
Wilcoxon signed-rank test calculator	Test paired measurements, or one sample against a value, with the Wilcoxon signed-rank test: V, an exact or normal p-value, a rank-biserial effect size and a pseudo-median interval.
Wilson proportion interval	Calculate a bounded confidence interval for a count out of a sample.
Text & writing39 toolsExplore category
Add line numbers	Number text lines with a custom start and separator.
Barcode check digit calculator	Generate or check EAN-8, UPC-A and EAN-13 arithmetic checksums.
Bulk text template	Turn rows of data into lists, messages and repeated snippets with one reusable template.
Character frequency table	Count exact characters and spot repeated whitespace or unusual code points.
Chat export viewer	Read a conversation export from ChatGPT, Claude or a list of messages: turns, roles, sizes and a plain transcript.
Email address list cleaner	Trim and deduplicate a simple address list while reporting syntax problems.
Find & replace	Replace literal text safely, with optional case matching.
Fuzzy string list matcher	Rank candidate names or labels by editable character distance.
Hidden character finder	Find zero-width, bidirectional, tag and other invisible or look-alike characters in text, and clean them out.
ISBN checksum and converter	Check ISBN-10/13 digits and convert compatible book number formats.
Lexical text similarity	Compare token overlap and frequency with three transparent scores.
List prefix & suffix	Add literal text before and after every line.
Literal text redactor	Replace a supplied list of private terms with a consistent marker.
Luhn checksum calculator	Generate or verify a modulo-10 check digit on a numeric string.
Markdown to plain text converter	Strip Markdown formatting from an AI answer or a README and keep the words.
Morse code translator	Translate letters and numbers to international Morse code.
N-gram frequency analyser	Find repeated word phrases or character sequences in local text.
Placeholder text generator	Create readable sample paragraphs for a layout.
Prompt version comparer	Compare two versions of a prompt word by word and see exactly what was added or removed.
Readability score calculator	Score text with Flesch reading ease, Flesch–Kincaid, Gunning fog, SMOG, Coleman–Liau and ARI.
Reading & speaking time	Estimate how long your text takes to read or say aloud.
Remove combining accents	Create a text copy with Unicode combining marks removed.
Remove duplicate lines	Keep one copy of each line while preserving its order.
Reverse text or line order	Reverse characters, words or lines in plain text.
Sort lines	Sort lists alphabetically or by numeric value.
Text case converter	Change text to sentence, title, upper or lower case.
Text comparison	See which lines differ between two pieces of text.
Text concordance / KWIC	Inspect every literal keyword occurrence with surrounding context.
Text line wrapper	Wrap paragraphs to a chosen character width.
Text pattern extractor	Pull email addresses, URLs, numbers, hashtags, IP addresses, dates or colours out of pasted text.
Title case converter for AP, Chicago, APA and MLA	Convert headlines to AP, Chicago, APA or MLA title case, or to sentence case.
Token and context-budget estimator	Estimate how many tokens a text uses and how much of a model’s context window it takes, with a stated margin of error.
Unicode character inspector	Inspect code points, names for common controls and UTF-8 bytes.
Unicode escape converter	Encode text as Unicode escapes or decode them without executing code.
Unicode text normaliser	Compare canonical or compatibility Unicode forms and export normalised text.
URL slug generator	Turn a title into a clean, readable URL slug.
Whitespace cleaner	Tidy spaces and line endings without retyping your text.
Word & character counter	A little clarity for essays, posts and everything you write.
Word frequency counter	Count repeated words with Unicode-aware word segmentation.
Travel & transport6 toolsExplore category
Aerodynamic drag & power	Calculate drag and steady power from a supplied drag coefficient and area.
Cycling gearing calculator	Relate chainring, sprocket, wheel rollout and cadence to geometric speed.
EV charging time & cost	Estimate an energy top-up using average power, efficiency and your tariff.
Tyre size comparison	Compare nominal geometry and speed ratios for two metric radial sizes.
Vehicle ownership cost	Combine depreciation and your running-cost assumptions over an ownership period.
Wheel width & offset comparison	Compare nominal inner and outer rim-edge positions.
Weather & air6 toolsExplore category
Dry-air sound speed	Estimate ideal sound speed from a supplied air temperature.
Heat index calculator	Combine air temperature and humidity using the NWS calculation.
Humidity & dew point	Translate relative humidity and dew point with an over-water model.
Vapour pressure deficit	Compare air and leaf saturation pressure with actual air moisture.
Wind chill calculator	Estimate the NWS wind-chill index within its stated input range.
Wind direction & components	Convert meteorological wind direction into east/north components, or back.

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