Bra Size Calculator

Calculate your bra size by measuring your underbust and bust. Italian and European size conversion.

How to Calculate Your Bra Size

Wearing the right bra size is essential for comfort and posture. Yet estimates suggest over 70% of women wear the wrong size. With two simple measurements you can find your exact size.

How to Take Measurements

Use a soft measuring tape:

Underbust: position the tape horizontally just below the bust, snug but not tight. Exhale normally and read the measurement.
Bust: position the tape at the fullest point of the bust without compressing. Ideally wear an unpadded bra.

Cup Size

The cup indicates bust volume and is determined by the difference between bust and underbust:

Difference (cm)	Cup
12.5	AA
15	A
17.5	B
20	C
22.5	D
25	E
27.5	F
30+	G

Fit Tips

The band should be horizontal across the back
Straps should not dig in or slide off
The cup should fully contain the bust without lateral overflow
Size may change over time: re-measure every 6-12 months or after significant weight changes

Frequently Asked Questions

How do I measure my bra size?▼

Take two measurements with a soft tape: 1) Underbust, measured horizontally just below the bust. 2) Bust, at the fullest point while wearing an unpadded bra. The difference determines the cup; the underbust determines the band size.

What do the cup letters mean?▼

Cup letters indicate bust volume based on the bust-underbust difference: AA (~12.5 cm), A (~15 cm), B (~17.5 cm), C (~20 cm), D (~22.5 cm), E (~25 cm), F (~27.5 cm), G (over 28.75 cm). Each increment is 2.5 cm.

Why does my size change between brands?▼

Each brand has its own fit standards and production tolerances. Bra style (push-up, balconette, triangle) also affects fit. The calculated size is a starting point -- always try on before buying.