What Size Button Do I Need If I Don’t Have the Original?

Replacing a missing button can be difficult when the original size is no longer available.

Here are several practical ways to estimate the correct size.

Check the Garment Type

Most garments tend to follow fairly consistent button size ranges.

Garment Common Button Size
Shirts 11.5–12.5 mm
Jackets 18–23 mm
Coats 23–25 mm or larger

These ranges are not fixed rules, but they can provide a useful starting point when selecting replacement buttons.

Measure the Buttonhole

The button should usually be slightly larger than the buttonhole.

If the button is too small, it may slip out more easily. If it is too large, fastening may feel tight or difficult.

As a general guide, a button that is around 1–2 mm larger than the buttonhole is often suitable.

Use a Reference Object

If a ruler is not available, comparing the size with common objects such as coins can provide a rough estimate.

This method is not precise, but it can help narrow down the likely size range.

Consider Thickness

A replacement button should fit comfortably through the existing buttonhole.

If the replacement is significantly thicker than the original, fastening may feel tighter even when the diameter is similar.