Bias Tape Calculator

Bias tape is cut on the 45° grain so it stretches smoothly around curves. The continuous-bias method sews a square into a tube and spirals one long strip — far less waste than cutting individual strips.

Approximate yield equals the square's area divided by strip width. A 18-inch square cut into 2-inch strips yields roughly 162 inches of bias before seam losses — about 4.5 yards.

Strip width is the cut width before folding. Single-fold and double-fold binding use different finished widths — enter the width you actually cut, not the finished binding size after pressing.

Worked example with defaults: 18-inch square, 2-inch strips → 18 × 18 ÷ 2 = 162 inches (~4.5 yards). Seam joins and trimming consume a few inches — buy or cut extra for large projects.

Smaller squares yield less total length but waste less fabric on small bindings. A 15-inch square at 2-inch strips gives 112.5 inches (~3.1 yards). Larger squares are more efficient for long quilt borders.

The continuous method starts by cutting the square diagonally, offsetting pieces, sewing a seam, and marking parallel lines. Online tutorials walk through the tube step — this calculator only estimates yield from area ÷ width.

For quilt binding, measure the quilt perimeter and compare to calculated yield before cutting. Mitered corners and joining tails eat a few inches — if the perimeter is 200 inches, an 18-inch square at 2-inch strips gives 162 inches and you will need a second square or a longer strip source.

Limits: does not account for seam allowance within strip width or fabric lost in the diagonal seam. Actual yield is slightly less than the formula; add 5–10% for safety on long bindings.