Belt Size Calculator
Find the belt size that actually fits. Enter your pant waist size (the classic +2 rule) or a tape measurement taken around where you wear your belt, in inches or centimeters, and get the size to order in US inches, cm, and EU sizing.
Example: with Size or measurement 34 · What you entered Pant / jeans waist size · Unit inches → Belt size to order: 36 in.
- In centimeters91 cm
- EU belt sizeEU 90
- Fit checkA size 36 belt puts the middle hole at about 36 in — you should have one or two holes of room in each direction
Computed by the calculator below using its default values. Change any input to see your own numbers.
Belt size = pant size + 2 in, rounded up to the even sizes belts are sold in. Belts measure from the buckle fold to the middle hole, which is why your pant size alone runs small.
Why a belt is two inches bigger than your pants
Belt sizes measure the strap from where it folds at the buckle to the middle hole. Your pants, meanwhile, are labeled with a waist number that sits under the fabric, and the belt has to travel over the waistband, through belt loops, and around whatever is tucked in. That path runs about two inches longer than the pant label — hence the near-universal retailer rule: order your pant size plus two.
A tape measurement beats the rule when vanity sizing muddies things. Run the tape through your belt loops over the clothes you actually wear, and that number in inches is your belt size directly — the calculator just rounds it up to the even sizes belts come in.
How it’s calculated
Belt size = pant waist size + 2 in (a measured waist converts directly), rounded up to the next even inch, since US belts sell in even sizes. cm = inches × 2.54. EU belt size = the belt length in cm rounded to the nearest 5, which is how European belts are labeled (85, 90, 95...).
Brand sizing varies an inch either way — when a marked pant size and a tape measurement disagree, trust the tape.
Pant size to belt size
| Pant waist | Belt size | EU belt |
|---|---|---|
| 30 in | 32 in | 80 |
| 32 in | 34 in | 85 |
| 34 in | 36 in | 90 |
| 36 in | 38 in | 95 |
| 38 in | 40 in | 100 |
| 40 in | 42 in | 105 |
Belt = pant size + 2 in; EU = belt length in cm rounded to the nearest 5. Matches standard menswear sizing charts.
Common mistakes
- Ordering your pant size: a 34 pant needs a 36 belt — the two-inch rule exists because belts measure buckle to middle hole.
- Measuring your bare waist when you wear pants at the hip; run the tape through the belt loops instead.
- Confusing belt size with total strap length — the tip past the last hole adds several inches that do not count.
- Rounding down between sizes: a belt should close on the middle hole, so always size up.
Frequently asked questions
What size belt do I need for a 34 waist?
A 36. The standard rule is pant size + 2 inches, because belt sizing runs from the buckle fold to the middle hole and the belt travels over your waistband.
What is the belt size formula?
Belt size = pant waist size + 2 in, rounded up to the next even size. If you measured with a tape through your belt loops, that measurement itself is the belt size.
How do EU belt sizes work?
They state the buckle-to-middle-hole length in centimeters, rounded to the nearest 5 — an EU 90 matches a US 36. The calculator converts automatically.
Where should a belt fasten?
On the middle hole of five, leaving room to tighten or loosen a notch. If you are on the last hole either way, the belt is the wrong size.