Reference Chart

Bra Size Chart

Read your band from your underbust and your cup from the difference between your bust and underbust. Inches and centimeters, with US, UK, EU, FR, AU and JP equivalents.

Last reviewed on 28 April 2026.

Every bra size is built from two measurements. The band is the snug measurement around your ribcage, just under the bust. The cup is the difference between your full bust and that band measurement. The two charts below convert each measurement into a size; if you have not measured yet, start with how to measure your bra size or skip straight to the calculator.

Band size chart (underbust → band)

Find your underbust measurement, then read across for the band number in each system. Bands are even numbers; round to the nearest one.

Underbust (in) Underbust (cm) US / UK EU / JP FR AU
27–2868–732860756
29–3074–783065808
31–3279–8332708510
33–3484–8834759012
35–3689–9336809514
37–3894–98388510016
39–4099–103409010518
41–42104–108429511020
43–44109–1134410011522
45–46114–1184610512024
47–48119–1234811012526

Cup size chart (bust − underbust → cup)

Subtract your underbust from your full bust and find the difference below. Cup letters match across systems up to D, then diverge.

Difference US UK / AU EU / FR / JP
0 in (0 cm)AAAAAA
1 in (2.5 cm)AAA
2 in (5 cm)BBB
3 in (7.5 cm)CCC
4 in (10 cm)DDD
5 in (12.5 cm)DDDDE
6 in (15 cm)DDD / FEF
7 in (18 cm)GFG
8 in (20 cm)HFFH

Note: cup letters above D vary by brand, especially in US sizing where DDD, DDDD, and F/G are used inconsistently. The conversion chart shows how each system maps step by step.

Rather not do the arithmetic? Enter your two measurements:

Calculate My Size

Find the guide for your exact size

Each size on BraCalc has its own page with measurements, sister sizes, international conversions, and fit notes. Jump to a few common ones below, or open the full bra size index.

32B · 32C · 34B · 34C · 34D · 34DD · 36C · 36D · 36DD · 38C · 38D · 40D

Frequently asked questions

How do I read a bra size chart?

Use two measurements. Find your underbust in the band table to get your band number. Then subtract your underbust from your full bust and find that difference in the cup table to get your cup letter. Together they make your size, such as 34C.

What is the average bra size?

Average measured size has drifted upward over time and varies by country, but in the US and UK it is commonly cited around a 34DD/34E. Averages are not targets — the right size is whatever your own measurements give.

Is a bra size chart the same in every country?

No. Band numbers differ (the US and UK use inches, the EU and Japan use centimeters, France adds 15 to the EU number, Australia uses a small even scale) and cup letters diverge above D. The conversion chart lines them up side by side.