Seam Allowance Calculator
Calculate the total extra fabric needed for seam allowances across all pattern pieces. Enter piece count, seam allowance width, and total seam length.
Inputs
Results
Extra Fabric (Total)
250 in
How to Use This Calculator
- Enter the number of pattern pieces in the garment.
- Set the seam allowance (inches) -- standard: 5/8 in US patterns, 1.5 cm European patterns.
- Enter total seam length (inches) (sum of all seams in the garment).
- Review extra fabric in inches and yards consumed by seam allowances and average seam per piece.
- Add seam allowances to pattern pieces before cutting -- most commercial patterns include them, but fashion patterns may not.
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