CraftSewing & fabric
Rectangular fabric yardage
Plan fabric length for identical rectangular pieces, including edge allowances, extra fabric and lengthwise shrinkage.
Your results
Assumptions & limits
Pieces keep the same orientation; rotation, pattern matching and irregular shapes are excluded. Use width after allowing for crosswise shrinkage. Shrinkage applies to length only. Round the final purchase up to your supplier’s increment.
Formula
cutWidth = w + 2s; cutLength = l + 2s; across = floor(F / cutWidth); rows = ceil(q / across); length = rows × cutLength ÷ (1 − shrink/100) × (1 + extra/100)
- w
- Finished piece width
- l
- Finished piece length
- s
- Allowance on each edge
- F
- Usable fabric width
- q
- Number of pieces
- shrink
- Lengthwise shrinkage (%)
- extra
- Extra allowance (%)
Worked example
w = 10 in; l = 20 in; s = 0.5 in; q = 6; F = 44 in; extra = 10%; shrink = 0%. → 4 × 2; 46.2 in = 1.28333333 yd.
Results show up to 8 decimal places. Small values use scientific notation; calculations use unrounded factors.