Boneyard Tools

Elastic Length Calculator for Waistbands

Work out how much elastic to cut for a snug waistband or cuff. Cut a little shorter than the body part so it holds, then add a small overlap to join the ends.

How to size elastic to cut

  1. Enter the body measurement of the waist, wrist or ankle in inches.
  2. Set the snug reduction percent, around 10 percent for a comfortable hold.
  3. Add an overlap for joining the ends, then read the cut length.

Examples

30 inch waist with a 10 percent snug and 1 inch overlap

Waist 30 in, snug 10 percent, overlap 1 in
Stretched 27 in, cut 28 in

Frequently asked questions

Why cut elastic shorter than the body measurement?

Elastic has to pull the fabric in to stay up. Cutting it a little shorter, often about 10 percent, gives a snug hold without digging in. Softer or wider elastic usually needs less reduction.

How much snug reduction should I use?

Around 8 to 12 percent suits most waistbands. Use less for delicate elastic or a relaxed fit, and more for a firm hold. Try a length around the body first if you are unsure.

What is the overlap for?

The overlap is the extra length where the two ends cross so you can sew them together securely. About 1 inch is common; use less for narrow elastic and more for wide elastic.

How is the cut length worked out?

The stretched length is the body measurement reduced by the snug percent, so a 30 inch waist at 10 percent gives 27 inches. The cut length adds the overlap, giving 28 inches to cut.

Does this work for cuffs and sleeves too?

Yes. Use the wrist or ankle measurement in place of the waist. Cuffs often want a slightly firmer hold, so a slightly higher reduction can help them stay in place.

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