Bra Size Calculator
Calculate your bra size based on band and bust measurements. Get accurate cup size and band size recommendations.
Published by:
isCalculator Editorial Team
Was this calculator helpful?
How to use this tool?
How to Use the Bra Size Calculator
- Enter your underbust measurement (band size) in the first field. Measure snugly around your ribcage, just under your bust.
- Enter your bust measurement in the second field. Measure around the fullest part of your bust.
- Select your unit (Inches or Centimeters) from the dropdown. The calculator automatically converts centimeters to inches.
- Click "Calculate" to see your results.
- Band size is your underbust measurement rounded to the nearest even number (e.g., 32").
- Cup size is determined by the difference between bust and band measurements (e.g., 4" difference = D cup).
- Sister sizes show alternative band/cup combinations that fit similarly (e.g., 34C = 32D = 36B).
Understanding the Results
Note: Bust must be larger than band. All inputs must be positive numbers.
Previous Results
| Result | Inputs | Date |
|---|
Frequently Asked Questions
Measure snugly around your ribcage, just under your bust. Ensure the tape is level and snug but not tight. Round to the nearest even number for band size.
Measure around the fullest part of your bust, keeping the tape parallel to the floor. Do not pull too tight.
Sister sizes are alternative bra sizes that have the same cup volume but different band sizes. For example, if your size is 34C, sister sizes are 32D (smaller band) and 36B (larger band).
