Find your EU bra size from two measurements — the band comes from your under-bust and the cup from the difference between your bust and under-bust.
Enter your measurements
Enter your under-bust and bust in cm. The EU band and cup update instantly.
Measure snugly around the ribcage under the bust for the band, and around the fullest point for the bust; the cup comes from the difference between the two. Sizes vary between brands and models, so use this as a guide and try before you buy.
Bra size: 75BInformational tool. Estimates your EU bra size from two measurements you enter. Sizing differs between brands, models and materials — treat the result as a starting point and try before you buy. Instant, no account.
The size has two parts. The band is your under-bust circumference rounded to the nearest 5 cm. The cup comes from the difference between your bust and under-bust in centimetres:
For an under-bust of 75 cm and a bust of 87 cm: the band is 75 and the difference (87 − 75 = 12 cm) gives a B cup — so 75B.
Take two measurements with a soft tape, ideally braless or in an unpadded bra. Measure snugly around your ribcage directly under the bust for the band, then loosely around the fullest point of the bust. Keep the tape level and breathe normally.
The band equals your under-bust measurement rounded to the nearest 5 cm (so 73 or 77 both become 75). The cup letter comes from the difference between your bust and under-bust: each 2 cm step raises the cup by one letter.
The number is the band — roughly your under-bust in centimetres (75 cm here). The letter is the cup, which reflects how much larger the bust is than the under-bust. So 75B means a 75 band with a B cup.
Subtract your under-bust from your bust. Under 10 cm is AA; 10–11 cm is A; 12–13 cm is B; 14–15 cm is C; 16–17 cm is D; 18–19 cm is E; 20–21 cm is F, and so on, adding one letter every 2 cm.
Brands cut and grade their bras differently, and stretch varies with fabric and style. A size that fits perfectly in one label may feel tight or loose in another, so always try the bra on when you can.
If your under-bust sits between two bands, the tool rounds to the nearest 5 cm. If a cup feels in-between, try the sister sizes — going down a band usually means going up a cup, and vice versa, for a similar volume.