Quilt Binding Calculator

Binding runs around the perimeter of the quilt — 2 × (width + length) — plus extra for the mitered corners and the diagonal join where the two ends meet. Most quilters add 10–12 inches of slack for a standard quilt; a king size or wide sashing borders justify 14. Then divide by the usable length of one strip: a strip cut across 42-inch-wide quilting cotton yields about 40 inches once the selvage is trimmed away.

The default 2½-inch strip width suits a standard ¼-inch seam and produces a finished binding of about ⅜–½ inch on the front. Mini quilts often use 2-inch strips; a chunky ¾-inch finished binding wants 3-inch strips. Whatever you enter, the fabric total is simply strips × strip width, converted to yards and rounded up to the nearest ⅛ — the increment most quilt shops will cut.

Take a throw quilt that finishes at 60 × 72 inches, bound with 2½-inch strips cut from 40-inch usable width. The perimeter is 2 × (60 + 72) = 264 inches. Add 10 inches for corners and the join: 274 inches of binding. Divide by 40 and you get 6.85 — so cut 7 strips. Seven strips at 2½ inches is 17½ inches of fabric length, or 0.486 yards — buy half a yard and you will have the scraps for the diagonal joins and a practice corner.

Cutting tip: join the strips with diagonal seams pressed open, not end-to-end square joins — the bulk of seven layered seams will show through the binding. And cut the strips on the straight grain for a quilt with straight edges; reserve bias binding (cut at 45°, which needs roughly √2 ≈ 1.4× the fabric) for scalloped or curved edges.