Cut Length
37.5"
Cut Width
46.4"
Extra Length
+1.5"
Cotton typically shrinks 3–5%. Pre-wash and dry before cutting to avoid surprises in your finished project.
| Fabric | Length % | Width % | Range |
|---|---|---|---|
| Cotton | 4.0% | 3.0% | 3–5% |
| Linen | 5.0% | 4.0% | 3–10% |
| Wool | 7.0% | 5.0% | 5–10% |
| Polyester | 0.5% | 0.5% | 0–1% |
| Rayon/Viscose | 5.0% | 4.0% | 3–8% |
| Denim | 5.0% | 3.0% | 3–10% |
| Desired | Cut At | Extra |
|---|---|---|
| 12" | 12.5" | +0.5" |
| 24" | 25.0" | +1.0" |
| 36" | 37.5" | +1.5" |
| 45" | 46.9" | +1.9" |
| 60" | 62.5" | +2.5" |
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Inputs
Result
This cotton swatch shrank 4.2% in length and 3.1% in width, which is typical for unwashed cotton. Total area lost is about 7.1%, meaning a 36×45" piece became 34.5×43.6" after the first wash.
Inputs
Result
To end up with 36×45 inches after washing cotton (4% length, 3% width shrinkage), cut at 37.5×46.4 inches. That extra 1.5 inches in length and 1.4 inches in width compensates for shrinkage.
Inputs
Result
Wool’s higher 7% length shrinkage means cutting 4.5 inches extra on a 60-inch piece. Width shrinkage at 5% adds 2.4 inches. Pre-wash wool on a cold delicate cycle to get this shrinkage out before your project.
Cotton typically shrinks 3–5% in length and 2–4% in width after the first hot wash and dry cycle. The average is about 4% lengthwise. Pre-washed or "sanforized" cotton shrinks less than 1%. Always pre-wash cotton before cutting to avoid surprises in your finished project.
| Fabric | Length Shrink | Width Shrink | Typical Range |
|---|---|---|---|
| Cotton | 4% | 3% | 3–5% |
| Linen | 5% | 4% | 3–10% |
| Wool | 7% | 5% | 5–10% |
| Polyester | 0.5% | 0.5% | 0–1% |
| Rayon | 5% | 4% | 3–8% |
| Denim | 5% | 3% | 3–10% |
Measure a swatch before and after washing. Shrinkage % = (original − washed) / original × 100. For example, a 36-inch piece that measures 34.5 inches after washing has shrunk (36 − 34.5) / 36 × 100 = 4.17%. Always measure both length and width separately since they often shrink at different rates.
Divide your desired finished measurement by (1 − shrinkage/100). For example, if you want 36 inches finished and cotton shrinks 4%, cut at 36 / (1 − 0.04) = 36 / 0.96 = 37.5 inches. This ensures the fabric ends up at your target size after washing.
| Desired Size | At 3% Shrink | At 5% Shrink | At 7% Shrink |
|---|---|---|---|
| 12" | 12.4" | 12.6" | 12.9" |
| 36" | 37.1" | 37.9" | 38.7" |
| 45" | 46.4" | 47.4" | 48.4" |
| 60" | 61.9" | 63.2" | 64.5" |
Yes. Wool shrinks 5–10% on average (7% typical), compared to cotton’s 3–5%. Wool also felts when agitated in hot water, which causes irreversible shrinkage beyond simple relaxation. Always hand-wash or use a wool cycle with cold water and lay flat to dry.
Yes, always pre-wash natural fibers (cotton, linen, wool, rayon) before cutting. Most shrinkage happens in the first wash. If you skip pre-washing and the finished garment shrinks, seams pucker and the fit changes. Polyester and polyester blends (>50% poly) rarely need pre-washing.
Fabric typically shrinks more along the length (warp direction) than the width (weft direction). This is because warp yarns are under higher tension during weaving. Cotton shrinks about 4% in length but only 3% in width. Always measure and calculate shrinkage for both directions independently.
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Last Updated: Oct 19, 2026
This calculator is provided for informational and educational purposes only. Results are estimates and should not be considered professional financial, medical, legal, or other advice. Always consult a qualified professional before making important decisions. UseCalcPro is not responsible for any actions taken based on calculator results.