Quilt Fabric Calculator

How the whole-quilt estimate works

This one adds up the whole top. From your block grid it figures the finished size, then estimates each fabric in turn — blocks, sashing, borders — and finishes with binding and backing so you can buy everything in one trip.

A worked example: a 5 × 6 grid of 9″ blocks

No sashing, no borders, 40″ usable width — the calculator's defaults:

Add sashing or borders and the finished size grows in both directions at once — a 2″ sashing between every block adds 8″ across and 10″ down here, which is enough to push the backing into a third width of fabric. Change one number at a time and watch the backing line; that is where the cost jumps.

It's an estimate — and that's on purpose

Block fabric is a combined area estimate with cutting waste built in, because every block pattern pieces differently: a nine-patch and a storm-at-sea use the same finished area and wildly different amounts of fabric. Treat the block figure as a shopping guide, not a cut list. For an exact cut list, use your pattern's cutting chart, then come back here for borders, binding and backing, which are geometric and therefore exact.

Choosing a size before you start

If you are designing rather than following a pattern, pick the finished size first and work backwards to the grid — it is much easier than discovering your throw is 4″ too narrow for the couch. The quilt size chart lists the standard mattress and throw dimensions, and fabric pull planning covers choosing the fabrics themselves once the yardage is settled.

Common mistakes

Forgetting that borders are doubled. A 4″ border adds 8″ to the width and 8″ to the length, not 4″. Buying block fabric to the estimate exactly. Buy a little over; cutting waste varies with the block. Ignoring directional prints. A print that must run one way can need 25% more fabric because you lose the option to rotate pieces. Not accounting for shrinkage. If you prewash, buy the extra before you wash, not after.

Common questions

Why is the block fabric a single combined number?

Because the split between your fabrics depends entirely on the block design, which the calculator does not know. Once you have the total, divide it by your pattern's proportions — or use the pattern's own cutting chart.

Does this include sashing and border fabric separately?

Yes — enter sashing and border widths and each is estimated on its own line, because those are strip-based and can be computed exactly.

How much extra should I buy?

A quarter yard over on each main fabric is a reasonable cushion for a first quilt, and leftovers go into the binding or a pieced back.