Find your bra size from your underbust and bust measurements, with US, UK and EU sizes and sister sizes for brands that fit differently.
About this tool
Find your bra size from band and bust measurements in US, UK and EU sizing.
How to use Bra Size Calculator
- Choose centimeters or inches.
- Measure snugly under the bust and loosely around the fullest point.
- Read your size and the sister sizes.
Worked example
An underbust of 30 in and bust of 36 in suggests a 30DD in US sizing.
What are sister sizes?
Sizes with the same cup volume on a different band, such as 32C and 34B. Try them when the band fits badly.
Why do brands fit differently?
Sizing is not standardized, so always check the brand’s own chart and try before buying where possible.
- Bra Size Calculator — Find your bra size from band and bust measurements in US, UK and EU sizing.
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