How do I work out my belt size from my waist?

The standard rule is to add two inches to your trouser waist size. So a 34-inch waist usually takes a 36-inch belt, which puts the buckle on the middle hole.

What belt size do I need for a 34-inch waist?

A 36-inch belt (waist + 2 inches), which is roughly 90 cm in EU sizing and an L in letter sizing.

What does EU belt size in centimetres mean?

EU belts are labelled by their length in centimetres, rounded to the nearest five. The tool converts your belt length in inches to cm and rounds, so a 36-inch belt is about 90 cm and a 38-inch belt about 95 cm.

How are the S–XL letter sizes assigned?

They map to the belt size in inches: up to 30 in = XS, 31–34 = S, 35–38 = M, 39–42 = L, 43–46 = XL and above that XXL.

Can I enter my waist in centimetres?

Yes. Choose the waist (cm) option and the tool converts to inches (÷ 2.54), adds 2 inches, and shows all the equivalent belt sizes.

Should I size up for a thick belt or heavy buckle?

The waist-plus-two rule is a starting point. Very thick belts or chunky buckles can fit slightly differently, so check the middle hole lands comfortably at your natural waist.

Is my measurement saved?

No. The conversion runs entirely in your browser and nothing is uploaded.

Belt Size Converter — Gera Tools

Belt size converter

A belt should be about two inches longer than your trouser waist so the buckle lands on the middle hole. This converter applies that rule and shows your matching US/UK inch size, EU centimetre size and S–XL letter size — handy when shopping across regions where belts are labelled differently.

How it works

Everything is resolved to a belt length in inches first:

belt size (in) = waist (in) + 2

If you enter your waist in centimetres it is converted (÷ 2.54) before adding 2 inches; if you enter an existing belt size it is used directly. The EU size is the belt length converted to centimetres and rounded to the nearest 5 cm, and the letter size is assigned from the inch belt size.

Example

A 34-inch waist:

US/UK belt = 34 + 2 = 36 inches
EU belt = round(36 × 2.54 / 5) × 5 ≈ 90 cm
Letter = M

Waist (in)	Belt (in)	EU (cm)	Letter
30	32	80	S
34	36	90	M
38	40	100	L
42	44	110	XL

All calculations run in your browser — nothing is uploaded.