QuiltM8

Quilt maths that is exact, works with no signal, and does not want an account.

Binding length, backing yardage, how many 5″ squares a fat quarter really gives you — answered in the fractions you cut in, with the working shown so you can check it against your own.

Works offline·no account·one-time purchase

In development A closed test on Google Play is the next step. Try the binding calculator ↓

What it works out

26 of its 31 calculators are free — all of them, forever, by machine-checked promise. The paid packs are the work around the answer. Six of the free ones run right here on this site:

How much binding? Strips and yardage for a bound edge Free · try it here How much backing? Panels, seam direction and yardage Free · try it here How wide do I cut the borders? Butted or mitred, one round Free · try it here What do I cut for half-square triangles? 2, 4 or 8 at a time Free · try it here How many strips, and how much fabric? Strips and yardage for N pieces Free · try it here What does a fat quarter really give me? How many pieces from a fat quarter Free · try it here
…and the rest of the pack Flying geese, QST, square-in-a-square, on-point setting, sashing and layout, bed sizes, resizing, batting, bias binding, spacers, strip rolls, a seam-allowance check, precut money maths, a longarm ballpark, postage weight. Free in the app
The paid packs The Project Pack (€7.99) keeps a whole quilt together — one shopping list, one rounding, a printable cut sheet. The Business Pack (€4.99) prices your work. Both €9.99, once. 🔒 One payment, no subscription

Try it here — this is the real engine

This is the app's own arithmetic, running in your browser. Type your quilt's size and watch the answer change; open Show the maths to see every step that produced it.

"

"

"

Type it the way you say it — 2 1/2, 2.5 or 6,5 all read the same.

The usual assumptions · usable width of fabric · how joins are counted · corners and tail · flat allowance
"

Counting every join is more accurate and buys a little more; the flat allowance is what quilting books print.

"

"

You need
5/8 yd
fabric to buy
8 strips · 20"

Perimeter: 264" · Cut in total, joins included: 295" · Joins: 7 joins · Lost per join: 3" · Lost to joins: 21" · Usable binding after joins: 299"

Cross-grain binding, cut across the width of fabric. For a curved edge you want bias binding instead.
Show the maths
1Perimeter — 2 × (60" + 72")264"
2Lost to joins — 7 joins × (2 1/2" + 1/2")21"
3Binding needed — 264" + 10" (corners) + 21" (joins)295"
4Strips — 295" ÷ 40" = 7 3/8 → round up8
5Fabric used — 8 × 2 1/2"20"
6Fabric to buy — 20" → round up to the next 1/8 yd5/8 yd

Cross-grain binding, cut across the width of fabric. Every join costs a strip width plus two seam allowances, and each extra strip adds a join.

The fat-quarter trap

A fat quarter and a quarter yard of the same fabric hold the same area. Cut 5″ charm squares from each and they stop being equal — whole pieces are what you sew with, and whole pieces are what QuiltM8 counts. Both grids below are computed, not drawn.

Fat quarter · 18″ × 21″

12 pieces

Quarter yard · 9″ × 40″ usable

8 pieces
4″ strip — no 5″ square fits

Same fabric, same square: 50% more usable pieces from the fat quarter — which is why a per-yard price comparison misleads, and why the app compares cost per usable piece instead. Step the patch size yourself →

On the phone

These are the real screens, at the text sizes people actually use — not tidied-up drawings of them.

Why the numbers are worth trusting

Every sum is worked out twice by different hands, and the two are compared against 6749 worked examples before any release goes out. Where an answer depends on something we cannot know — your shop's prices, your cotton's weight — it says so on the screen where you read it, rather than guessing. And every formula names where it came from: 69 published sources, readable without paying for anything.

The long answer →

What it asks of your phone

Nothing that isn't yours to give. There is no account and no sign-in; no analytics, no advertising and no crash reporting, so nobody is told which tools you open. It does not use your camera, location, contacts or microphone. Everything is worked out on the phone, and nothing you type leaves it. When you buy a pack the payment runs through the Google Play app already on your device — we never see your card, your name or your address. Your projects stay a file you can export whenever you like.

What it costs

Nothing you need to answer a question. 26 of the 31 calculators are free forever, and so are saving, searching and export. The Project Pack (€7.99) keeps a whole quilt together — one shopping list, rounded once, and a cut sheet you can pin above the table. The Business Pack (€4.99) is for quilters who sell. Both together, €9.99, once. There is no subscription and there never will be.

Email us to hear when it ships — that reaches a person, not list software, and we keep nothing else.

Questions quilters ask

What can QuiltM8 work out?

26 free calculators: binding, backing, borders (butted or mitred), half-square and quarter-square triangles, flying geese, square-in-a-square, on-point setting, sashing and layout, bed sizes with drop, what a precut really yields, block resizing, batting, bias binding, spacers, strip rolls, a seam-allowance check — and the money questions: what a precut costs per usable square, wide backing against piecing, a longarm ballpark, postage weight — plus kitting a whole quilt from a block recipe, and the patchwork units chart. Five more come with the paid packs: pricing your work, project costs, stash value, time, and the full longarm quote.

Does it think in quilters’ fractions?

Yes — exactly. The arithmetic is exact fraction arithmetic, answers come back in the eighths and sixteenths you cut in, and the keypad has a fraction row. Typing works too: it reads 2 1/2, 2-1/2, 2½, 2.5 and 2,5.

Does it keep cut size and finished size straight?

Yes — every field says which one it means, every time. A 6″ finished half-square triangle is cut at 6 7/8″ and trimmed to 6 1/2″; the app tells you all three so you never hold them in your head.

Which way does it round?

The safe way, always: fabric and cut sizes round up (a little too much is a scrap; a little too little is a ruined cut), counts round the way that never promises a piece that isn’t there, and a shopping list is rounded once, on the total.

All of them →