Bra Size Calculator

Measure your band and bust and get your bra size in US, UK and EU sizing, plus a sister-size fit tip. Free, private bra size calculator — nothing is uploaded, works right in your browser.

Enter both measurements.

How to use the Bra Size Calculator

  1. 1

    Measure snugly under your bust for the band.

  2. 2

    Measure around the fullest part for the bust.

  3. 3

    Enter both in inches or centimetres.

  4. 4

    See your US, UK and EU size instantly.

Frequently asked questions

How do I measure my band?

Wrap the tape snugly around your ribcage directly under your bust, keeping it level all the way around.

What is sister sizing?

If a size feels off, going down a band and up a cup (or vice versa) keeps a similar cup volume with a different band fit.

Is it accurate?

It's a solid starting estimate — cup and band fit varies by brand and style, so try a couple of nearby sizes.

Tips & discussion

Share a trick, ask a question, or help others get more out of this tool.

Log in to share a tip or ask a question.

Loading tips…