Title Nine Bra Fit Calculator

Determining your bra size is the first step in finding the right fit. We’ve made crunching the numbers easy with our Bra Fit Calculator.


All it takes is three quick measurements! Need more detailed directions? Everything is explained below.

We've done our best to take out the guesswork and make finding your cup-band bra size simple. Push-ups and padding can skew things, so pull on a shelf bra camisole or your best fitting everyday bra.

Step 1: Measure around your chest, just under the arms and above the bust. Make sure that the tape measure is taut and is straight across your back, but not tight, or that could result in a squeeze later. Breathe out, relax your shoulders. We'll get through this together. If the measurement is an odd number or a half size, round it up to the next even number (for example, 33 will actually be 34). This number is known as your band size. Unsure you've got it right? Take a seat - our chests expand some when seated.

Step 2: Now it's time to measure your cup size. Measure around the fullest point of your bust. This could be at the nipple, but everyone's body is different. This will be one of two measurements that you need to determine your cup size.

Step 3: For the final measurement, measure just under the bust around your ribcage.

Got the measurements? Good. It's time to calculate your bra size.

  • Women can experience upwards of nine major bra size changes in their lives, so it's a good idea to get sized at least once a year.
  • Whether you're shopping for an everyday bra or a sports bra, the size you wear is the same in both. No need to size down for more support!
  • Bras do eventually get worse for the wear due to all that washing. It's important for your girls that no sports bra ever celebrate a birthday!

Buying a sports bra and not sure where to begin? Our Sports Bra FAQ can help.