Clothing fit

Bra Size Calculator

Estimate band and cup size from underbust and bust measurements.

Fit varies by brand

Bra sizing systems differ by country, brand, style and personal fit preference. Use this as a starting size, not a final fitting guarantee.

Example

If underbust is 32 inches and bust is 37 inches, the 5-inch difference gives a starting cup estimate around DD/E in many US-style size charts.

How to use the result

Use the estimate to choose a few nearby sizes to try. Band fit, cup shape, strap placement and fabric stretch can all change what feels right.

Common mistakes

Do not assume one brand's size will fit the same in every style. Measure with the tape level and snug, but not tight enough to compress the body.

Limitations

This is a clothing fit estimate, not a health or body assessment. Country sizing systems and brand conversions can differ.

Last reviewed: 2026-05-17

Before relying on this result

Use this calculator together with the formula, assumptions, limitations and examples on the page. If the topic involves health, tax, lending, investment, legal, safety or current-rate decisions, treat the number as an estimate and check the relevant primary source or professional guidance.

Calculator metadata last reviewed: 2026-05-14.