Quilt Binding Calculator

How the binding yardage calculation works

Binding is the strip of fabric folded over the raw edges of a finished quilt sandwich to enclose and protect them. Getting the yardage right before you cut means one less trip to the fabric store mid-project.

The math is straightforward. Start with the quilt’s perimeter — twice the width plus twice the height. Add an overage allowance for joining strips and finishing the end connection (10 inches is the standard minimum). Divide that total length by your fabric width to find how many strips to cut. Multiply the strip count by the cut width to get total fabric inches, then divide by 36 to convert to yards. Finally, round up to the nearest 1/8 yard — quilters always buy a little more than the minimum.

Choosing the right strip width

The standard double-fold binding strip is cut at 2.5 inches. Folded in half and wrapped to the back, this produces a finished binding face of about 3/8 to 1/2 inch — the look most quilters expect. For a narrower, more delicate binding use 2.25 inches. For a chunkier, more visible edge use 2.75 inches.

Single-fold binding, used on table runners and lightweight projects, is cut at 1.25 to 1.5 inches. Enter the actual cut width in the calculator and it will give you the correct yardage regardless of style.

Joining strips: 45° diagonal vs. straight

Once you have cut your WOF strips, you need to join them end-to-end into one long continuous strip. There are two methods:

• 45-degree diagonal join (recommended): Place two strips right sides together at a right angle, overlapping the ends. Sew from corner to corner on the diagonal, trim to 1/4-inch seam, and press open. The diagonal distributes seam bulk over a longer distance, so the join is nearly invisible on the finished edge.
• Straight join: Sew strip ends directly together. Faster, but the overlapping seam allowances create a bulky ridge that can be felt and sometimes seen through the quilt back.

Almost all experienced quilters use the diagonal join. The few extra seconds it takes pays off with a professional finish.

Worked examples: crib to king

These calculations use the defaults: 2.5-inch strip width, 42-inch fabric width, 10-inch overage.

Always pre-wash binding fabric before cutting — cotton typically shrinks 3–5%, which can make a borderline calculation come up short.

Tips for accurate binding

• Use a walking foot when machine-stitching binding to the quilt front — it feeds all layers evenly and prevents waviness.
• Start attaching binding in the middle of one side, not at a corner. This makes it easier to finish the joining seam neatly.
• Miter corners by stopping 1/4 inch from the corner, folding the binding up at 45 degrees, then back down along the next edge before continuing to sew.
• If you plan to hand-stitch the binding to the back, leave it a touch fuller — cut strips at 2.625 inches instead of 2.5 inches for a little extra ease.