About QuiltMath

QuiltMath exists because quilting math is the part of quilting people hate, and because cutting expensive fabric wrong hurts twice: once in the wallet and once in the heart.

What this site is

QuiltMath is a collection of free quilting calculators: backing, binding, batting, borders, precuts, half square triangles, flying geese, setting triangles, sashing, and more. Every tool takes your exact measurements and returns cutting-ready numbers with the work shown. No accounts, no paywalls, no "unlock premium to see your answer." You type, it computes, you cut with confidence.

Who builds it

QuiltMath is built and maintained by King Winston Media, an independent studio that builds free, fast, single-purpose web tools. We are calculator people who took quilting math seriously: every formula on this site was implemented from first principles, then verified against published quilting references before launch.

How the calculators are verified

Three layers, every time. First, each formula is cross-checked against multiple independent published quilting references; where conventions differ (overhang amounts, trim allowances), we state the assumption plainly on the tool's page. Second, every calculator carries a suite of hand-computed test cases, calculated on paper before the code existed, that must pass before any update ships. Third, the famous results act as referees: our precut math reproduces the classic jelly roll race quilt size exactly, and our setting triangle numbers match the charts quilters have trusted for decades. Each tool's "Sources and methodology" section shows its formula, because a calculator that hides its math is asking for faith it has not earned.

What we believe about quilting math

It should be done once, correctly, by something that does not get tired at 10pm. Rounding should always go up, because nobody has ever been sad about an extra quarter yard. And the result should arrive with a little reassurance attached, because behind every yardage question is a person about to take a rotary cutter to fabric they love.

Contact

Questions, corrections, or a calculator you wish existed? Write to hello@quiltmath.net. Corrections get priority; if a number on this site is wrong, we want to know before anyone cuts.

Last reviewed: June 10, 2026