How to calculate it
Pieces per row = floor(usable fabric width ÷ piece width). Rows = ceil(quantity ÷ pieces per row). Multiply rows by piece length, then by 1 + waste percentage ÷ 100. Divide inches by 36 for yards.
Worked example
Eight 12 × 18 in pieces fit three across 44 in fabric. Three rows take 54 in; with 10% extra, buy at least 59.4 in, or 1.65 yd before shop rounding.
Before you cut or buy
- Use cut dimensions, including seam allowances, rather than finished pattern measurements.
- This rectangular layout does not account for curved shapes, nap, directional prints or pattern matching; lay out your pattern pieces before purchase.
Common questions
Why does my sewing pattern need more fabric than this estimate?
The calculator packs rectangular cut pieces in rows. Garment pieces, curves, nap and one-way motifs restrict rotation and may waste more fabric. Use the pattern's cutting layout as the final check.
Do I include seam allowances in piece dimensions?
Yes. Enter each piece's dimensions as you will cut it, including seams and hems. Using finished measurements will understate the yardage.
Use your own measured materials and pattern instructions. Estimates cannot account for every variation in technique, shrinkage or layout.