Fabric Shrinkage Yardage Calculator

Measure shrinkage instead of guessing by fiber name

Mark a test rectangle along the fabric's length and width, record both dimensions, then wash and dry it using the intended care method. Shrinkage percentage = (before - after) / before × 100. A length changing from 10 inches to 9.2 inches gives 8%; a width changing from 10 to 9.5 inches gives 5%. These are illustrative observations, not cotton or linen defaults.

Use the pattern's length requirement for the correct fabric width, size, and nap direction. If it already includes extra cutting allowance, avoid adding that allowance again. This tool compensates for measured dimensional changes; it does not arrange pattern pieces or infer yardage from garment measurements.

Formula and purchase rounding

Prewash yardage = required washed yardage × (1 + allowance / 100) / (1 - length shrinkage / 100). Divide by the shop increment, round upward to a whole increment, then multiply back. Washed width = usable starting width × (1 - width shrinkage / 100). Width margin = washed width - layout minimum. Cost = rounded purchase yardage × price per yard.

Adding 8% to a length is not equivalent to compensating for 8% loss. The remaining fraction is 0.92, so divide by 0.92. Length and width losses are independent inputs. More length cannot guarantee that an individual wide pattern piece fits across a narrower bolt.

Worked example: three yards needed

For 3 yd after washing, 10% extra length allowance, and 8% length shrinkage, unrounded yardage is 3 × 1.10 / 0.92 = 3.5869565 yd. Buying in quarter-yard increments means 3.75 yd, costing $45 at $12/yd. Expected washed length is 3.45 yd. A 60 in usable width shrinking 5% becomes 57 in, leaving 3 in above a 54 in layout minimum.

When the width check fails

A negative margin is a layout warning, not a recommendation to buy the displayed length blindly. Choose wider fabric or redraw the layout and enter its revised length requirement. Rotating pieces may violate grainline or nap instructions. Directional prints, matching motifs, and irregular fabric defects can require a separate layout even when width passes.

Assumptions and limitations

The arithmetic assumes uniform shrinkage matching your test, one continuous purchase, and no subsequent stretching. Supported shrinkage is 0–50% in each direction, length 0.01–1,000 yd, widths 1–500 in, allowance 0–100%, increments 0.01–10 yd, and price 0–10,000 USD/yd. Expansion and negative rates are not supported. Results show two decimals but use unrounded values internally.

No empirical textile shrinkage table is used, so no outside authority is required for the formula. Follow the fabric's care label and test before cutting. Costs exclude delivery, taxes, and notions. If a shop sells meters, convert the requirement and selling increment to yards before use; one yard is 36 inches. Do not mix a meter price with a yard length.

Related material planning

The wallpaper roll calculator handles wall drops and pattern repeats, while the fence picket spacing calculator handles discrete board layouts. Neither estimates textile shrinkage.

Last updated: 2026-10-09. Check the actual cutting layout before purchasing.