Free tool
Sewing Unit Converter
Convert sewing measurements between inches, fractions, centimeters, millimeters, yards and meters — and see the nearest standard seam allowance.
Results round to the nearest ⅛", the smallest mark on most sewing rulers.
Seam allowances at a glance
| Seam allowance | Metric | Used for |
|---|---|---|
| ¼" | 6 mm | Quilting, patchwork |
| ⅜" | 1 cm | Many indie and European garment patterns |
| ½" | 1.3 cm | Bags, home décor, many tutorials |
| ⅝" | 1.5 cm | Big 4 commercial garment patterns |
Need to know how much fabric that pattern takes? Try the fabric yardage calculator.
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