How to use this calculator
Enter the finished dimensions of one rectangle and the seam allowance added to every edge. Measure usable fabric width after excluding selvages. The calculator places all pieces in the same orientation across the fabric.
The formula
A worked example
Twelve finished 10 × 12 inch pieces with 0.5 inch seams need 11 × 13 inch cuts. Four fit across 44 inches. Three rows use 39 inches, or 1.0833 yards. The result rounds up to 1.09 yards so rounding does not leave you short.
Assumptions & limitations
No automatic rotation or layout optimization. Excludes shrinkage, print matching, nap direction adjustments, cutting gaps, and mistakes. Add those allowances and round up to your supplier’s purchase increment before buying fabric.
Common questions
Can rotating pieces save fabric?
Sometimes. Swap the finished width and length to compare, provided the fabric grain and pattern allow it.
Should I enter the full advertised width?
Use the width you can actually cut after excluding unusable selvages.
Units reference
The calculation follows the method above. This reference supports the units and conversions.
NIST: units and conversion factors ↗Formula and worked example checked against automated test cases. About our methodology.