Bra Size Calculator
This calculator estimates bra size based on bust size and band size (frame size). To ensure accuracy, measure to the nearest ¼ inch or ½ cm. This calculator provides results for the United States, the United Kingdom, European Union, France, Belgium, Spain, Australia, and New Zealand.
The bust size is the loose circumference measured around the chest over the fullest part of the breasts, while standing straight with arms to the side, and wearing a properly fitted bra.
The band or frame size is the firm circumference, fitted not tightly, measured directly underneath the breasts.
Bra Size Converter
Use the following to convert the bra sizes between different locations.
Incorrect bra fit
Surveys and studies often cite that anywhere between 70-85% of women wear incorrectly fitted bras. While data collection methods between sources are not consistent and these percentages may be inflated, incorrectly fitted bras are nonetheless a significant issue. Studies have revealed that the most common mistake when selecting a bra is choosing too large a back band and too small a cup. Part of the issue is the lack of standardization: band and cup sizes vary largely between countries and even manufacturers, so a 34B from two different companies may not fit the same person. Signs of an incorrectly fitted bra include the band digging into the torso or sliding upwards, red marks, shoulder or neck pain, the breasts overflowing around the edges of the bra, and the bra's center panel not lying flat.
Bra size
The two major aspects of bra size are the band size and the cup size.
Band size (frame size)
The band size is the size of the bra band around the torso. Band sizes come in different measurements in different countries. Refer to the table below for some size measurements, though some variation from the published measurements is possible.
| Band Size | FR/BE/ES | EU (Standard 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 |
Cup size
The cup size can be calculated using the difference between bust size and band size. Refer to the tables below.
| Bust/band difference in inches | US cup size | UK/AU cup size |
| <1 | AA | AA |
| 1 | A | A |
| 2 | B | B |
| 3 | C | C |
| 4 | D | D |
| 5 | E or DD | DD |
| 6 | F or DDD | E |
| 7 | G or DDDD | F |
| 8 | H | FF |
| 9 | I | G |
| 10 | J | GG |
| 11 | K | H |
| 12 | L | HH |
| 13 | M | J |
| 14 | N | JJ |
| Bust/band difference in cm | Continental Europe cup size |
| 10-11 | AA |
| 12-13 | A |
| 14-15 | B |
| 16-17 | C |
| 18-19 | D |
| 20-21 | E |
| 22-23 | F |
| 24-25 | G |
| 26-27 | H |
| 28-29 | I |
| 30-31 | J |
| 32-33 | K |