Bra Size Calculator

Find your perfect bra size using band and bust measurements. Convert between US, UK, and EU sizes.

Band Size (underbust) (cm)

Bust Size (fullest point) (cm)

How to Measure

Measure your band size (underbust) snugly around your ribcage
Measure your bust at the fullest point, keeping the tape level

Free Bra Size Calculator — Find Your Perfect Fit

Finding the right bra size is essential for comfort and support. Studies show that up to 80% of women wear the wrong bra size. Our Bra Size Calculator helps you find your perfect fit using simple measurements.

All you need is a soft measuring tape. Measure your band size (underbust) and bust size (at the fullest point), then enter the measurements here. The calculator shows your size in US, UK, and EU systems.

The cup size is determined by the difference between your bust and band measurements. Each inch (2.5 cm) of difference represents one cup size, starting from AA.

Remember that bra sizes can vary between brands and styles. Use this calculator as a starting point and always try on bras before purchasing when possible.

FAQ

How do I measure my bra size at home?+

Use a soft measuring tape. For the band, measure snugly around your ribcage just under your bust. For the bust, measure at the fullest point with the tape parallel to the ground. Wear a non-padded bra for accuracy.

What if I'm between sizes?+

If you're between sizes, try both the smaller and larger size. Consider "sister sizes" — for example, 34C, 32D, and 36B have similar cup volumes.

Do bra sizes vary between brands?+

Yes, bra sizes can vary significantly between brands and styles. Use this calculator as a guide, and always try on bras when possible.

How often should I measure my bra size?+

It's recommended to re-measure every 6-12 months, as your body can change due to weight fluctuations, hormones, aging, or exercise.

What are sister sizes?+

Sister sizes are bra sizes that have the same cup volume but different band sizes. For example, 32D, 34C, and 36B are sister sizes — the cups hold the same volume.