What belt size do I need for my pants size?

The usual rule is to buy a belt one to two inches larger than your pants waist size, so a size 34 pair of pants takes a size 36 belt. That puts your natural waist near the middle hole, leaving room to adjust either way. Belt sizes are normally even numbers, so round up to the next even size if your pants size is odd.

How is belt size measured?

A belt is measured from the fold where the buckle attaches to the middle hole, not the very end. That measurement is the belt size. If you measure an old belt this way and it fits well, order the same size. Otherwise take your pants size and add two inches.

Is belt size the same as waist size?

Not quite. Your true waist measurement and your labelled pants size can differ, and a belt sits slightly outside the trousers, so belt sizes run about two inches above your pants size. If you measure your bare waist, add one to two inches to allow for clothing and a comfortable fit.

Belt Size Calculator

This belt size calculator turns your pants waist size into the belt size you should buy, so you order once and get a belt that sits right. The rule it uses is the one menswear and womenswear guides agree on: your belt size runs about two inches larger than your labelled pants size, because a belt threads around the outside of the trousers and you want your natural waist to fall near the middle hole. Buying a belt the same number as your pants tends to leave you buckling on the very first hole, and going too large leaves a long tail flapping past the loops. Enter your usual pants waist size in inches and the calculator returns the recommended belt size, rounded up to the next even number because most belts are sold in even sizes, and it also shows the figure in centimetres for New Zealand shops that label in metric. If you would rather measure than guess, run a tape around your bare waist where the belt will sit, or measure a belt you already like from the buckle fold to the hole you use, and compare that with the result here. The tool is a starting point for ordering online: brands cut leather and webbing slightly differently, so check each maker's own size chart, and remember a belt with several holes gives you room to move as the fit changes.

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Your pants waist size

Enter the waist size printed on trousers that fit you well. If you only have your bare waist measurement, add one to two inches before entering it.

36 in

recommended belt size to buy

Your pants size34 in

Belt size in centimetres91 cm

Fit allowance added2 in

Belts are sold in even sizes, so the result rounds up to the next even number. Brand size charts differ, so confirm against the maker's chart before you order. Guide only.

How it works

The calculator takes your pants waist size and adds two inches, the standard allowance that puts your waist near the centre hole of the belt. It then rounds up to the next even number, since belts are almost always stocked in even sizes, and that rounded figure is the belt size to order. The centimetre value is the same size multiplied by 2.54 and rounded to the nearest whole centimetre, useful when a New Zealand or European retailer labels belts in metric. The fit allowance shown is simply the difference between the belt size and your pants size, so you can see how much room has been built in.

Worked example

Say you wear size 34 trousers. Add two inches and you get 36, which is already an even number, so the recommended belt size is 36 inches. In metric that is 36 times 2.54, which is 91.44 centimetres, rounded to 91 cm. The fit allowance is 36 minus 34, or 2 inches, which places your waist at the middle hole with two or three holes spare on either side. If instead you wore size 33 trousers, adding two gives 35, which rounds up to the next even size of 36, so you would order the same belt.

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