Pant Size Calculator

A pant size is a short code for the body a pair of pants is cut to fit. Men's sizes are usually two numbers in inches, waist first and inseam (inside leg length) second, so 32 x 30 means a 32 waist and a 30 inseam. Women's US sizes are numbers such as 8 or 14 that point to a row on a brand's body chart. This calculator matches your tape measurements to published charts and converts the result.

What Pant Size Measures

It matches your waist, hips and inseam to one brand's chart per group, Nike for men¹ and L.L.Bean for women², because no shared US sizing standard is enforced. It cannot see the cut, rise or stretch of the pants, so it gives a size to try first, not a promise of fit.

The Formula

Men's waist size = the size in Nike's chart whose body waist is closest to yours (if you enter hips too, the larger of the two sizes wins)

Men's inseam = your inseam rounded to the nearest whole inch

Men's EU size (Nike) = waist size + 18

Women's US size = the larger of your waist size and your hip size on L.L.Bean's chart

Women's UK and Australian size = US size + 4, and EU size = US size + 32

The women's conversions follow ASOS's international size chart³. Writing pant sizes as waist then inseam goes back at least to a 1950 US standard for men's work trousers, which listed sizes such as "30-32"⁴.

How This Calculator Computes Your Result

Pick men's or women's sizing, then type your numbers in inches or cm. The tool works in inches (cm / 2.54) and rounds nothing before matching. A value exactly halfway between two sizes goes to the larger one.

Men get a waist x inseam size, their real waist beside the label, and UK, EU, French and Italian sizes. Women get a US number and letter size, UK, EU and Australian sizes, a plus size (such as 18W) from US 16 up, and a petite, regular or tall length from height or inseam. Both get a European EN 13402 style label in cm.

What Your Result Means

In Nike's men's chart, each size is cut for a waist 1.5 inches larger than the label number¹. UK sizes use the same inch numbers.

Some brands label by the plain waist instead. ASOS sells a 32 to fit a 32 inch (81 cm) waist⁵, so your result shows both numbers. European numbers vary too, and Nike's own chart lists two for each size, one EU and one French and Italian¹.

Women's sizes follow L.L.Bean's body chart², with ASOS's conversions³.

Plus sizes have their own chart, from 16W (waist 35, hips 45 inches) to 26W (waist 45, hips 56.5 inches)². Lands' End UK pairs 16W with UK 20⁶. Length comes in three cuts.

These two brands set their height cut-offs about an inch apart⁶ ⁷, so the tool trusts your inseam over your height when you give both. Petite and tall cuts also change the rise. In Lands' End's chart, petite rise is 1 inch shorter than regular and tall rise 1 inch longer, at every size where both are listed⁶.

How to Measure Correctly

Use a soft tape over light underwear, level and snug but not tight.

• Natural waist: the narrowest part of your torso, usually where your body bends when you lean to the side¹. The European sizing standard places it between the top of the hip bones and the lowest ribs, with the stomach relaxed⁸.

• Where your pants sit: low and mid rise pants sit below the natural waist, and Lands' End UK measures there⁶. If you wear pants low, take this number too and compare it with the brand's chart.

• Hips: put your heels together and run the tape around the widest part of your hips⁶.

• Inseam: lay pants that fit you well flat and measure the inside leg seam from crotch to hem⁷ ⁹. On your body, ASOS measures from the crotch to the ankle bone⁵. Do not go to the floor. That is the European standard's body inside leg⁸, which runs longer than a pants inseam.

• Rise: on flat pants, front rise runs from the crotch seam up to the top of the waistband, and back rise runs up the back⁴. A shorter rise sits lower.

Why the Label Waist Is Not Your Real Waist

The 1950 US standard treated the label as a minimum, so a 30-32 pair had to measure at least 30 inches around the waistband⁴. It was voluntary, and labels have drifted. In 2010, an Esquire writer measured pants labeled with a 36 inch waist and found about 37 inches at H&M and about 41 at Old Navy¹⁰. Women's pants are no steadier: when Kinley measured 1,011 pairs, every labeled size varied, and pricier pants generally ran larger¹¹. Pants need some room to move, but a gap of several inches means the label no longer tells you your waist.

Standards exist but are neither public nor binding. ASTM International publishes body measurement tables for adult men in short, regular and tall¹² and for women's misses sizes 00 to 20¹³. They are sold as paid documents and brands follow them by choice, which is why this tool uses published brand charts.

What to Do Between Sizes

Brands disagree. L.L.Bean tells men to order the next larger size⁹, Lands' End UK tells women to choose the smaller unless they want a looser fit⁶, and Nike says smaller for tighter and larger for looser¹. The tool shows both sizes when you are near the line. Without stretch, the larger size is safer, since a loose waist can be belted or taken in.