Bra Size Calculator

Bra Size Calculator is a clean, respectful tool that estimates your bra band and cup size from two simple measurements — completely offline. Enter your underbust and bust, and instantly see an estimated size in US, UK and EU sizing.

WHAT YOU CAN DO
• Enter your band (underbust) and bust measurements
• Switch between inches and centimeters with one tap
• See an estimated US size, plus matching UK and EU sizes
• Read a clear breakdown of your band and bust difference
• Browse reference charts for cups and band conversions

HOW TO MEASURE
A built-in guide explains how to measure correctly: the band snugly around the ribcage just under the bust, and the bust loosely over the fullest part, ideally in a non-padded bra. Accurate measurements give a better estimate.

LEARN AS YOU GO
The Learn tab explains, in plain language, the difference between band and cup, why sizes differ between brands and regions, and how sister sizes work so you can fine-tune the fit.

APPROXIMATE BY NATURE
There is no single global bra-sizing standard. US, UK and EU systems letter the larger cups differently, and every brand cuts its bras a little differently. The results in this app are approximate estimates and a starting point — always try a bra on for the real fit. This app does not provide medical or professional fitting advice.

PRIVACY
The app collects no personal data and works fully offline — your measurements never leave your device and are not stored after you close the app. Ads are served by Google AdMob, which may use an advertising identifier (advertising ID) as described in Google's policies.

Light and dark themes, a tiny download, and a calm, clutter-free design. Download Bra Size Calculator and find your starting size with confidence.