Belt Size From Your Waist Measurement

Turn a tape measurement or a trouser tag into a US and EU belt size.
The two starting points give different answers, and this page keeps them apart.

Belt Size

This page asks where your number came from, because a tape measurement through the belt loops and the size printed on your trousers are not the same thing and do not lead to the same belt. If you already have a belt size and only want it in another scale, the belt size converter takes belt size, EU centimetres, pin-to-hole length or trouser waist and fills in the rest as you type.

How Belt Size Is Determined

Belt sizing is one of the most misunderstood measurements in fashion. Most people buy a belt that matches the waist size of their pants, and end up with one that is too short.

The fundamental rule:

Belt size = Pants waist size + 2 inches

If you wear size 34 pants, buy a size 36 belt.

This ensures the buckle prong passes through the middle hole (hole 3 of 5), leaving room to loosen or tighten as needed.

Why the +2 rule works:

Belts are measured from the buckle pin to the middle hole, not to the end. With 5 holes spaced 1 inch apart, the middle hole is 2 inches from either extreme:

Belt length = Waist measurement + 2 (to reach middle hole)

Measuring for a perfect fit:

  1. Thread a fabric tape measure through your pants loops exactly where a belt would sit
  2. Note the length where it overlaps comfortably, not tight and not loose
  3. Round that to the nearest even number, and add nothing to it

Step 3 is where people go wrong. The +2 rule and the tape rule apply to two different numbers. Add two inches to the size printed on your trousers, because that label is smaller than the garment. Add nothing to a tape measurement taken through the loops, because the tape has already travelled around the waistband and your shirt, so it is the belt length you want. Do both and you end up with a belt a full size too long.

International belt sizing:

US/UK Size EU Size Trouser size it suits Tape through the loops
30 75 28 30 in
32 80 30 32 in
34 85 32 34 in
36 90 34 36 in
38 95 36 38 in
40 100 38 40 in

Those last two columns are the same belt described twice, and mixing them up is the mistake this whole page exists to prevent. A size 36 belt suits size 34 trousers, and a tape threaded through the loops of those trousers reads about 36 inches.

Belt width by pant style:

  • Formal trousers (narrow loops): 1–1.25 inch width
  • Casual chinos or jeans: 1.25–1.5 inch width
  • Work jeans and denim: 1.5–1.75 inch width
  • Western style: 2 inch and above

The width has to fit through the belt loops, so measure the loop opening if you are unsure. A 1.5 inch belt will not go through the loops on most dress trousers, and forcing it stretches them.


How we build and check this calculator

This calculator runs entirely in your browser, so the numbers you enter stay on your device. The math behind it is written by hand and tested against worked examples and standard references before the page goes live.

SuperGlobalCalculator is independently built and maintained. See how we build and verify our calculators.


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