Plan a quilt from block layout to binding
This kit follows the arithmetic of a straight-set patchwork quilt in the order you meet it at the cutting table: how big the quilt will be, how much fabric the pieces take, what pre-washing will do to your yardage and how much binding to cut. Each step opens a Toolmoz tool already filled with a worked example. Change the numbers to your own as you go.
The figures in the examples are common starting points, not rules. Block sizes, seam allowances and fabric widths vary between patterns, so follow your pattern wherever it differs.
- 5 steps
- About 20 minutes
- Runs on your device; nothing is uploaded
Review status. Not yet reviewed by a specialist in this craft. The arithmetic is checked by tests against independent calculations, but the practical advice is a starting point: if you can improve it, a pull request is welcome (see docs/niche-kits.md in the Toolmoz repository).
Before you start
The boxes are for you while you work. They are not saved and leave this page when you do.
The steps
Choose the layout and size
The number of blocks across and down, the finished block size and your seam allowance give the finished quilt size, how many blocks to make and the size to cut each block square.
Take from the result: The finished width and height, the block count and the cut square size.
Keep this page’s result on screen: in step 5 you can pass the finished width and height straight to the binding calculator with “Send result to…”.
Example loaded: Throw quilt: 5 × 6 blocks of 10 in. A straight-set throw, 50 × 60 in finished, thirty blocks cut at 10½ in.
If your blocks use half-square trianglesoptional
Two squares sewn together on a diagonal and cut apart give two triangle units. The tool gives the starting square size (including a trim allowance), how many pairs to cut and how many units you will have.
Take from the result: The starting square size and the number of pairs to cut. Skip this step if your pattern has no triangle units.
Example loaded: Half-square triangles, 3 in finished. Forty-eight 3 in half-square triangles, a common size for a sampler or scrappy quilt.
Work out how much fabric the pieces need
Pieces are cut from strips across the width of the fabric. The tool counts how many pieces fit across a strip once the selvedges are set aside, how many strips you need and how much length that takes, in inches and in yards.
Take from the result: The fabric length for each colour or print. Add up your colours, round up, and keep a margin for mistakes and for the shrinkage you work out next.
Example loaded: 2½ in squares from 44 in fabric. One hundred 2½ in squares (cut size, including seams) from fabric 44 in wide, allowing 1 in at each selvedge.
Allow for shrinkage
Measure a swatch before and after washing it the way you will wash the finished quilt. The tool turns the change into a percentage and tells you how much longer and wider to buy so the washed fabric still covers what you need.
Take from the result: The length and width to buy before washing. Use your own swatch figures in place of the example.
Example loaded: Example: a washed cotton swatch. A 20 cm square that came out 19.2 cm long and 19.6 cm wide, used to find how much to buy for a 150 × 140 cm finished piece.
Cut the binding
Binding runs round the whole edge: twice the length plus twice the width, plus extra for the corners and the final join. The tool turns that into the number of strips to cut across your fabric and the length of fabric they need.
Take from the result: The number of strips and the fabric length. If you used step 1 on this device, send it the finished width and height instead of typing them.
On the layout result use “Send result to…”, choose Quilt binding calculator, and send the finished height to “Quilt length (inches)” and the finished width to “Quilt width (inches)”.
Example loaded: Throw quilt, 50 × 60 in. Binding for a sofa throw: five 10 in blocks across by six down, 2½ in strips from 40 in of usable fabric.
When you have the numbers
What this kit does not cover
- Straight-set square blocks only, with no sashing, borders or on-point layouts.
- The cutting tools work in cut sizes, which include seam allowances. They do not model fabric stretch, bias edges or directional prints.
- Backing, batting and borders are not sized here.
Sources and further reading
The tools’ own pages explain their methods and list their sources. Presets are worked examples from the Toolmoz repository, each checked against an independent calculation.