One Measurement.
Your Exact Band Size.

Guessing your band size is the #1 reason bras feel wrong. Enter your underbust measurement and get an instant, accurate band size cross-checked across US, UK, EU and AU/NZ sizing.

  • ✓ Results in under a minute, no sign-up needed
  • ✓ Works in inches or centimetres
  • ✓ Cross-references UK, EU and AU/NZ equivalents

Calculate your band size

Measure with a soft tape, directly under your bust, over a well-fitted (or no) bra.

How We Calculate Your Band Size

Your band size comes from your underbust measurement the snug measurement directly under your bust, where the bra band sits. We round that number to the nearest whole inch, then add 4" if it's even or 5" if it's odd, giving you a standard, even band size (28, 30, 32, 34...). This is the traditional method used by most fitting guides and lingerie brands.

Step-by-Step: How to Measure Your Band

  1. Wear a well-fitted, non-padded bra (or none at all). A padded or ill-fitting bra will throw the measurement off.
  2. Wrap a soft measuring tape directly under your bust, around your rib cage, where the band of a bra would sit.
  3. Keep the tape parallel to the floor and snug against your skin not tight, not loose.
  4. Breathe out normally and read the number in inches or centimetres, then enter it above.

Band Size Reference Chart

Use this chart to double-check your result, or to compare band sizes across regions.

Underbust (in)US / UK BandEU BandAU/NZ Band
24–2528606
26–2730658
28–29327010
30–31347512
32–33368014
34–35388516
36–37409018
38–39429520

Frequently Asked Questions

Is band size the same in every country?

No. US and UK bands use the same numbers, but EU sizing switches to centimetres and AU/NZ uses its own smaller numbering that's why we show all three above.

Should the band feel tight?

It should feel snug and stay level all the way around, but you should be able to slide two fingers underneath it comfortably.

My band size changed is that normal?

Yes. Weight changes, posture, and even the bra brand you're comparing to can shift your band size by an inch or two. Remeasure every few months.