Seam allowance: how much to add

Seam allowance is the fabric outside the stitching line. Its size depends on construction, fabric and finishing method.

A reliable method

Simple home projects often use 1–1.5 cm. French seams, bulky fabrics and fitting adjustments may require more. Curtain hems are much deeper than ordinary side seams. Check whether a commercial pattern already includes allowances.

Use the calculation in practice

SzyjTo adds the selected allowance to every relevant edge.