Bra Size Calculator
Calculate your bra size from underbust and bust measurements with this free online bra size calculator. Get US, UK, EU, French and Australian sizes.
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How to use Bra Size Calculator
- 1Measure snugly around your ribcage just under the bust
- 2Measure loosely around the fullest part of your bust
- 3Enter both in inches or centimetres to see your size in every system
Frequently asked questions
How do I calculate my bra size?▾
Your band is your underbust measurement rounded to the nearest even inch. Each inch of difference between your bust and band is one cup size: 1 inch = A, 2 = B, 3 = C and so on.
What are sister sizes?▾
Sister sizes have the same cup volume on a different band. Going down a band and up a cup (e.g. 34C to 32D) keeps the cup volume the same.
Why are UK and US cup sizes different?▾
Both start the same up to DD. After that, the UK uses E, F, FF, G while the US usually uses DDD/F, G, H, so larger sizes differ by letter.
Embed Bra Size Calculator on your website▾
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