Do bra sizes vary between brands?

Yes, significantly. Sizing is not standardized across brands or even within the same brand across styles. Always try on or check the specific brand size guide.

What is sister sizing?

Sister sizes have the same cup volume but different band sizes. For example, 34C, 32D, and 36B all have the same cup volume. Go up a band and down a cup (or vice versa).

Bra Size Converter

Convert bra sizes between US, UK, EU, and French sizing systems based on band and cup measurements.

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US Band Size

US Cup (A=1, B=2, C=3, D=4, DD=5)

EU Band Size

UK Band Size34

French Band Size85

Bust Circumference (approx in)37 inches

View formula & how it works →

Bra Size Conversion

Band Size Conversions

US/UKEUFrench 327085 347590 368095 3885100

Cup Sizes

US and UK cup letters generally align through D/DD but diverge at larger sizes. EU uses A, B, C, D, E, F progression.

How to Measure

Band: Measure snugly around the ribcage just below the bust

Cup: Difference between bust measurement and band measurement (each inch = one cup size)

Example Calculation

Convert US 34C to other systems.

01EU band = (34-32) x 2.54 + 63 = 68 (round to 75)
02UK band = 34 (same as US)
03French band = 34 + 51 = 85
04Cup C is the same letter in US, UK, and EU

Frequently Asked Questions

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