Measure your band (underbust) and bust (overbust) sizes to find your bra size.
inches
inches
How to Measure
1. Measure your band size just under your bust, keeping the tape snug but comfortable.
2. Measure your bust size at the fullest part of your chest.
3. Subtract band size from bust size to find your cup size.
4. Use the chart below to find your cup letter.
Cup Size Chart (Difference between bust and band):
- Less than 1″ = AA
- 1″ = A
- 2″ = B
- 3″ = C
- 4″ = D
- 5″ = DD/E
- 6″ = DDD/F
- 7″ = G
About the Bra Size Calculator
Finding the perfect bra size can be tricky, but our free Bra Size Calculator makes it easy. By measuring your band (underbust) and bust (overbust) sizes accurately, you can discover your approximate bra size with the right band and cup combination.
To get started, use a soft measuring tape to measure just below your bust to find your band size, then measure around the fullest part of your bust for the bust size. Enter these values in inches, and the calculator will do the rest. It rounds the band size to the nearest even number since bra bands are usually sized in even numbers.
The difference between your bust and band size determines your cup size. For example, a difference of 1 inch corresponds to an A cup, 2 inches to a B cup, and so on, up to larger cup sizes. This tool uses a common cup size chart to give you an approximate size.
Remember, bra sizing can vary slightly between brands and countries, so this calculator provides a solid starting point. Always try on bras for the best fit and comfort.
Use this calculator to confidently shop online or in-store and make sure you pick the right size every time!