Wellness estimates

Bra Size Calculator

Find your bra size from your underbust (band) and fullest bust measurements. Use this Health estimates tool to enter your numbers, review the result, and understand the key assumptions before making the next decision.

What you get
A focused calculator, clear explanation, common questions, and useful next tools.
Quick intro
Calculator
Result
Explanation
Common questions
Related tools

Calculator tool

How this calculator works
The result depends on the numbers you enter and the assumptions shown below.

Band size is rounded to the nearest even number from your underbust measurement. Cup size is determined by the difference between bust and band: 1 inch = A, 2 = B, 3 = C, 4 = D, 5 = DD/E, 6 = DDD/F.

Review the inputs carefully and treat the output as an estimate. For decisions involving money, taxes, health, law, or security, compare the result with trusted professional guidance when needed.

Frequently asked questions

Should I measure in a bra or without?

Measure your underbust (band) snugly without a bra. Measure your bust at the fullest point while wearing a non-padded bra or bralette.