Health 5 Sizing Systems

Bra Size Calculator

Find your bra size from underbust and bust measurements. Converts between UK, US, EU, FR/ES/BE and AU sizing systems automatically.

Measurement Units

Underbust (ribcage) Measurement

Measure directly under your bust, as tightly as possible.

Bust Measurement

Measure loosely at the fullest part of your bust.

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Enter your measurements

Enter underbust and bust measurements to find your size across all major sizing systems.

Cup Size Guide (US/UK)

Bust-Band Diff.	US/UK Cup	EU Cup	FR Cup
0"	AA	AA	AA
1"	A	A	A
2"	B	B	B
3"	C	C	C
4"	D	D	D
5"	DD/E	E	E
6"	DDD/F	F	F
7"	G	G	G
8"	GG/H	H	H

US/UK	EU (cm)	FR/ES/BE	AU/NZ
28	60	75	10
30	65	80	12
32	70	85	14
34	75	90	16
36	80	95	18
38	85	100	20
40	90	105	22
42	95	110	24

Use a soft measuring tape. Wear a non-padded bra or no bra for accuracy.

Step	How to Measure	Result
1. Underbust	Wrap tape directly under bust - as firm as possible	Your band size base
2. Bust	Wrap tape at fullest point of bust - relaxed, not tight	Used for cup calculation
3. Calculate	Subtract underbust from bust	Difference = cup size

US/UK	EU (cm)	FR/ES/BE	AU/NZ
28	60	75	10
30	65	80	12
32	70	85	14
34	75	90	16
36	80	95	18
38	85	100	20
40	90	105	22
42	95	110	24

US/UK	EU (cm)	FR/ES/BE	AU/NZ
28	60	75	10
30	65	80	12
32	70	85	14
34	75	90	16
36	80	95	18
38	85	100	20
40	90	105	22
42	95	110	24

US/UK	EU (cm)	FR/ES/BE	AU/NZ
28	60	75	10
30	65	80	12
32	70	85	14
34	75	90	16
36	80	95	18
38	85	100	20
40	90	105	22
42	95	110	24