How do I know what size I am in different clothing brands?

Measure your chest or bust (tops) and waist (bottoms) in centimetres, then enter the number in the converter. It compares it against each brand’s size chart and shows the size to start with in each brand. The same body is often an M in one brand and an L in another — that’s normal.

If I’m a medium in one brand, what size am I in another?

Switch to “Convert my size”, pick the brand and size you know, and the tool maps it to a body measurement, then finds the closest size in every other brand. A Zara M lands near a Boohoo M (UK 12) and an H&M M, for instance.

Why is the same size different in every brand?

Letter sizes aren’t standardised. Each brand uses its own fit model and measurement ranges, and vanity sizing shifts labels. The centimetres are the reliable thing to compare, not the letter.

Are these size charts accurate?

They’re built from each brand’s own size guide where available, otherwise reputable aggregators (noted in Sources). They’re body — not garment — measurements, and fit varies by product (slim, oversized, tall). Use the result as a starting point and confirm on the brand’s chart for the specific item.

Can I see how a piece looks on me before I buy?

Yes. Paste the product link into wearfits.me and get a studio shot of you wearing it. It shows how the piece looks on you; it is a visual preview, not a size guarantee.

Guide

Clothing size converter

Updated 2026-11-05 · By WEARFITS

Find your size

Choose What size am I? to go from a measurement to a size, or Convert my size to go from a size you know in one brand to the others. Women’s and men’s tops and bottoms.

Sizes aren’t standardised between brands — results are a starting point, not a guarantee. Cut and fabric still vary by garment; the brand’s own chart for the exact piece is the final word.

How to measure

Chest / bust
Tape around the fullest part, level under the arms and across the shoulder blades. Drives tops and dresses.
Waist
Tape around the narrowest part of your natural waist, snug and level. Drives trousers, jeans and skirts.
Hip
Tape around the fullest part of your hips and seat. Useful to cross-check bottoms when waist and hip disagree.

Keep the tape firm but not tight, and measure over light clothing or skin. The full walkthrough, with inseam and sleeve, is in how to measure yourself. Buying shoes too? The shoe size converter and shoe size recommender on arfits.com do the same for footwear.

How the converter works

Every brand publishes a chart that maps body measurements to its sizes. The converter holds those charts in centimetres and, for each brand, picks the size whose measurement is closest to yours: chest or bust for tops, waist for bottoms (hip is shown to cross-check).

Spot-on — within 2 cm of the brand’s value for that size.
Close — within 5 cm.
Approx. — further away; you’re probably between sizes in that brand.
Between sizes — your measurement sits about halfway between two of the brand’s sizes, so neither is a clear pick.

In Convert my size mode it first turns your known size into its body measurement, then finds the closest size in every other brand. Between sizes? Size up for a relaxed fit, down for a fitted one.

Why sizes differ by brand

There is no legal or industry standard that says what a “medium” must measure. Each brand chooses its own fit model and its own measurement ranges, then prints a letter on the label. In the charts below, for example, a men’s M is listed for a 96–100 cm chest at H&M, 95–104 cm at Nike and about 102 cm at Zara and Lululemon.

Add vanity sizing — labelling a garment smaller than it really is, so the shopper feels good — and the letter on the tag means little on its own. That’s why the converter compares centimetres, not letters: your chest, waist and hips don’t change between websites; only each brand’s mapping does. More on this in Does it fit me?

Brand size charts in cm

The body measurements behind the converter. Chest or bust drives tops and dresses; waist (with hip as a cross-check) drives bottoms. Values are representative body measurements published by each brand — not garment measurements. See Sources.

FAQ

How do I know what size I am in different clothing brands?: Measure your chest or bust (tops) and waist (bottoms) in centimetres, then enter the number in the converter. It compares it against each brand’s size chart and shows the size to start with in each brand. The same body is often an M in one brand and an L in another — that’s normal.
If I’m a medium in one brand, what size am I in another?: Switch to “Convert my size”, pick the brand and size you know, and the tool maps it to a body measurement, then finds the closest size in every other brand. A Zara M lands near a Boohoo M (UK 12) and an H&M M, for instance.
Why is the same size different in every brand?: Letter sizes aren’t standardised. Each brand uses its own fit model and measurement ranges, and vanity sizing shifts labels. The centimetres are the reliable thing to compare, not the letter.
Are these size charts accurate?: They’re built from each brand’s own size guide where available, otherwise reputable aggregators (noted in Sources). They’re body — not garment — measurements, and fit varies by product (slim, oversized, tall). Use the result as a starting point and confirm on the brand’s chart for the specific item.
Can I see how a piece looks on me before I buy?: Yes. Paste the product link into wearfits.me and get a studio shot of you wearing it. It shows how the piece looks on you; it is a visual preview, not a size guarantee.

Sources

Each brand’s measurements come from its official size guide where that was accessible, or a reputable aggregator or retailer where it wasn’t (marked below). Links checked June 2026. Brands update their charts periodically — if a number looks off, the brand’s own current guide is the final word.