Quilt Binding Calculator
Calculate total binding length, the number of width-of-fabric strips, and the linear fabric needed for standard straight-grain binding joined diagonally.
Assumption: strips are cut across the usable width of fabric and joined with standard 45° diagonal joins. Each diagonal join is modelled as using approximately one strip width of binding length.
Required binding length = quilt perimeter + your extra joining / overlap allowance. The calculator increases the number of strips until their effective joined length is at least that amount.
Fabric purchase
Linear fabric needed for the strips equals strip count × strip width. The purchase suggestion rounds up to the next 0.1 metre or 1/8 yard.
Before cutting
Bias binding, very wide bindings, scalloped edges, curved edges or a non-standard joining method can require a different calculation. Measure your actual usable width of fabric after removing any selvedge you do not plan to use.
Worked example
A 150 × 200 cm quilt has a 700 cm perimeter. Add 25 cm for joining and overlap, and 725 cm of binding is required. With 6.5 cm strips cut across 106 cm usable fabric width, 8 strips are needed. They use 52 cm of linear fabric, so the purchase suggestion rounds up to 0.6 m.
Common question
Why does the calculator subtract strip width at each join? A standard diagonal join overlaps two strips by roughly one strip width, reducing their combined effective binding length.
Related quilting tools
Quilt Backing Calculator · Quilt Block Calculator · Fabric Yardage Calculator