Bra Size Calculator
Calculate your bra band and cup size from two simple measurements: your underbust, taken snugly just below the breasts, and your bust, taken across the fullest point. The band size comes from the underbust measurement rounded to a whole even number, and the cup size comes from the difference between bust and band, where roughly every inch of difference steps you up one cup letter. Enter both measurements in inches or centimeters, and this tool returns your US band and cup along with the total label such as 34C. Bra fit is personal and brands cut differently, so treat the result as a well grounded starting point and try sister sizes if the band feels tight or loose. Everything is computed locally in your browser and nothing you enter is stored or sent anywhere, with the size updating instantly as you type.
How to use Bra Size Calculator
- Measure your underbust in inches or cm.
- Measure your bust at the fullest point.
- Enter both measurements.
- Read your band and cup size.
Frequently asked questions
How is bra size calculated?
It uses the standard inch difference method: your underbust measurement sets the band, and the difference between bust and underbust sets the cup, with each inch of difference stepping up a cup.
Where do I take the measurements?
Measure the underbust snugly just under the breasts and the bust around the fullest point, both level and parallel to the floor.
Why do calculators disagree with brand fit?
Cup and band standards vary by brand and country, so this gives a reliable baseline you then fine tune with try ons or a brand size chart.
What is Bra Size Calculator?
Calculate your bra band and cup size from two simple measurements: your underbust, taken snugly just below the breasts, and your bust, taken across the fullest point. The band size comes from the underbust measurement rounded to a whole even number, and the cup size comes from the difference between bust and band, where roughly every inch of difference steps you up one cup letter.
Is Bra Size Calculator free to use?
Yes. Bra Size Calculator is completely free, with no sign-up and no usage limits.
Does Bra Size Calculator work in a web browser?
Yes. Bra Size Calculator runs in any modern web browser. There is nothing to download or install.
Is my data private with Bra Size Calculator?
Yes. Bra Size Calculator runs entirely on your device in your browser, so nothing you enter is uploaded to a server.
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