Enter your bust and band measurements to find your estimated bra size in several countries, or convert a size from one system to another.
Measure to the nearest ¼ inch or ½ cm. The bust is the loose measurement around the fullest part of the chest, and the band is the firm measurement directly under the bust.
Convert a bra size between sizing systems. This matches sizes by their position in each system's table.
Typical band sizes. Real sizes vary a little between makers.
| Band | FR/BE/ES | EU (EN 13402) | US and UK | AU, NZ |
|---|---|---|---|---|
| XXS | 75 | 60 | 28 | 6 |
| XS | 80 | 65 | 30 | 8 |
| S | 85 | 70 | 32 | 10 |
| M | 90 | 75 | 34 | 12 |
| L | 95 | 80 | 36 | 14 |
| XL | 100 | 85 | 38 | 16 |
| XXL | 105 | 90 | 40 | 18 |
| 3XL | 110 | 95 | 42 | 20 |
| 4XL | 115 | 100 | 44 | 22 |
| 5XL | 120 | 105 | 46 | 24 |
Stand straight with your arms at your sides. The bust measurement is the loose circumference around the fullest part of the breasts, wearing a well-fitted bra. The band, or frame, measurement is the firm circumference directly under the breasts, fitted snugly but not tight. Measure to the nearest quarter inch or half centimeter.
The band size is the band measurement rounded to a whole even number of inches, such as 32, 34 or 36. The cup size comes from the difference between the bust and the band: each inch of difference is one cup size, starting with AA at less than one inch, A at one inch, B at two inches, and so on. For a 38 inch bust and a 34 inch band, the difference is 4 inches, which is a D cup, so the size is 34D. European sizes use centimeters, with a 5 cm band step and a cup step of 2 cm.
Band sizes and cup letters are not the same everywhere. The US and UK use inches, and the UK cup letters double up, with DD, FF and GG, where the US uses DD/E, DDD/F and so on. The EU, France, Belgium and Spain use centimeters, with French band sizes 15 higher than the EU ones. Australia and New Zealand use dress-code numbers for the band. Some makers add four or five inches to the underbust to get the band size, which the second set of rows shows.
Studies suggest that a large share of women wear a bra that does not fit well, most often a band that is too big and a cup that is too small. Sizing is not standardized, so the same size from two makers can fit differently. Use the result as a starting point, try several sizes, and consider a professional fitting. Signs of a poor fit include a band that rides up or digs in, straps that dig into the shoulders, and cups that gap or overflow.
Measure your band under the bust and your bust at the fullest point. Round the band to an even number of inches for the band size, and use the difference between bust and band for the cup: 1 inch is A, 2 is B, 3 is C, 4 is D, and so on.
Sister sizes have the same cup volume with a different band. Going up one band size and down one cup, for example from 34C to 36B, keeps a similar cup volume.
They match up to D. After that, the US uses DD/E, DDD/F, DDDD/G and then H, while the UK uses DD, E, F, FF, G and so on.
Use the converter on this page. The EU band size is in centimeters: a US 34 band is an EU 75, and a US 36 is an EU 80.
There is no standard for bra sizes, so makers cut the band and cup differently. A 34B from two makers may not fit the same person.
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