What are common hem depths?

Trousers: 3–4cm. Straight skirts: 4–5cm. A-line skirts: 2–3cm. Circle skirts: 0.5–1cm (narrow rolled). Shirts: 1–2cm. The more curved the hem, the narrower it should be.

What is a double-turned hem?

A double-turned (or double-fold) hem folds the raw edge under once, then folds again by the hem depth. It encloses the raw edge completely. The total allowance needed is twice the finished hem depth.

When should I use a blind hem?

Blind hems are ideal for tailored garments where you do not want visible stitching on the outside. The stitches catch only a tiny amount of the outer fabric, making them nearly invisible. They work best on medium to heavy fabrics.

Hem tape (or hem webbing) is fusible tape placed between the hem fold layers. When pressed with an iron, it bonds the layers together without stitching. Buy tape slightly longer than the garment circumference.

SewCalcs

Hem Calculator — Hem Allowances & Types

Calculate hem allowances and fabric requirements for different hem types.

Garment Circumference

Full circumference at hem level

Hem Type

Hem Depth

Finished hem depth

How We Calculate This

Hem allowance depends on the hem type:

Single turn: Hem depth + 0.5cm turn-under
Double turn: Hem depth × 2
Narrow rolled: 1.5cm total
Blind hem: Hem depth + 1cm
Faced hem: 1.5cm (separate facing piece)

Frequently Asked Questions

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Last updated: February 2026

All calculations are estimates. Always verify quantities before cutting or purchasing fabric.