Data & CSV

CSV rule validator

Check required fields and declared column types without uploading records.

Your inputs

Your CSV

Up to 25 MB per file, 50,000 data rows, 200 columns and 2 million data cells. Fully blank rows and columns are ignored before row, column and cell limits are checked. Individual tools may have smaller result or chart limits.

Or choose a CSV file

Column separator

Rules CSV: Column,Type,Required

Or choose a CSV file

Results update as you type. Larger files run when you press Update result.

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Your result

LOCAL & PRIVATE

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A clear answer. Here’s how.

Rules name existing columns once, with Type string/integer/number/boolean/date/email and Required yes/no. Empty means exactly zero characters; unlisted columns are ignored. Integers are decimal digit strings, numbers are finite decimals up to magnitude 1e100, booleans are lowercase true/false, dates are strict Gregorian ISO dates, and email uses a pragmatic ASCII syntax check. Counts every violation; result/export includes the first 1,000. Does not check email delivery.

See a worked example

Worked example

A fixed demonstration, separate from the values you enter above.

Your CSV

ID,Name,Team,Amount,Date
001,Ada,Design,120,2026-01-05
002,Sam,Writing,80,2026-01-06
003,Jo,Design,150,2026-01-07

Column separator

Comma

Rules CSV: Column,Type,Required

Column,Type,Required
ID,integer,yes
Name,string,yes
Amount,number,yes
Date,date,yes

Example result

Example result
CSV row	Column	Value	Issue

0 violations across 3 data rows. At most 1,000 violations are exported; unlisted columns are ignored. Email checks are syntactic only.