CraftM8 › Why the numbers are right
Why the numbers are right
You are about to cut into fabric you paid for. A calculator that is wrong costs you the fabric, the afternoon, and the trip back to the shop — so here is exactly why these numbers can be trusted, and how to catch us if they are not.
Every sum is done twice, by different hands
Each calculator exists in two independent versions: the one in the app, and a second one written separately from the published formula and worked examples. The two are compared against thousands of worked examples — 6749 of them for quilting alone — and if they ever disagree by so much as an eighth of an inch, the release stops until somebody works out which one is wrong. Checking your own work with your own method finds nothing; that is why there are two.
The calculators on this site are not a third version. They are the app's own arithmetic, running in your browser, put through the same worked examples every time this site is built.
Fractions stay fractions
There is no rounding-off hiding inside these sums. 276 divided by 40 is kept as an exact fraction, not as 6.8999999, and it only becomes a decimal at the moment it is shown to you. That is why answers come back in the eighths and sixteenths you actually cut in, and why the same question always gives the same answer.
Rounding goes the safe way, on purpose
Fabric and cut sizes round up — a little too much is a scrap, a little too little is a ruined cut. Counts round whichever way cannot promise you a piece that is not there. And a shopping list is added up first and rounded once, at the end, which is worth an eighth of a yard on the worked example and more on a long list.
An answer that is not exact says so
Where something depends on what we cannot know — your longarm quilter's rates, the weight of your particular cotton — the answer is labelled an estimate, and it names the soft figure. The label travels with the number onto the screen and into anything you print. Exact and estimated answers are never allowed to look alike.
Where each formula came from is published
Every calculation names its source — 69 of them across the quilting app — and you can read all of them without paying for anything. Provenance is not something a paywall should sell.
Don't take our word for any of it
Open your browser's network tab on any page here: it asks nothing of anybody but this site. No analytics, no fonts fetched from a tech giant, no tracking pixels. View the page source and the numbers are printed in it, not fetched from a server that could quietly change them. Every answer opens into its own working. And if you find a number that is wrong, the address in the imprint reaches the person who can fix it — in the app and on this site together.