Hem Allowance Calculator
Find cut length from finished length, or calculate how much you can let out an existing hem.
Results are estimates. Always add extra for shrinkage, mistakes, and pattern matching.
How to Use the Hem Allowance Calculator
New Hem: Select a garment type for a suggested hem allowance, or choose a hem type and enter a custom amount. Enter your desired finished length to get the required cut length.
Let Out Existing Hem: Enter the current finished length and how deep the existing hem is. The calculator tells you the maximum length you can gain by letting out the hem.
Hem Allowance Guide by Garment Type
| Garment | Typical Hem | Fold Type | Notes |
|---|---|---|---|
| Shirt / Blouse | ½–1" | Double fold | Narrow for woven shirts |
| Dress | 1–2" | Single or double | Depends on skirt fullness |
| Pants / Trousers | 1.5–2" | Single fold | Wider for letting out later |
| Skirt | 1–2" | Single or double | Flared skirts: narrow hem |
| Curtains | 3–4" (double) | Double fold | Adds weight for drape |
Single vs. Double Fold
- Single fold: Fabric edge turned up once. Raw edge is hidden inside (use with serger or zigzag stitch).
- Double fold: Fabric edge turned up twice, enclosing the raw edge. Cleaner finish, uses more fabric.