UK to US bra size converter

Shopping from a brand in another country? Your band number stays the same. Cup letters match up to DD, then the UK doubles its letters (E, F, FF, G) while the US adds Ds (DD, DDD) and jumps to G. Type your size and we'll translate it into all six labels.

34DDDUS · converted from UK 34E
UK
34E
US
34DDD
EU
75F
FR
90F
AU
12E
JP
G75

After DD the letters split: UK 34E is US 34DDD.

One size, six label systems. The band number and cup volume never change; only the letters do.

UK and US cups, letter by letter

Each row is one inch more between bust and band. Rows where the UK and US letters differ are marked.

The cup ladderSame band, one inch per step. EU letters for comparison.
Bust minus bandUKUSEU / FR
1 inAAA
2 inBBB
3 inCCC
4 inDDD
5 inDDDDE
6 inEDDD (differs from UK)F
7 inFG (differs from UK)G
8 inFFH (differs from UK)H
9 inGI (differs from UK)I
10 inGGJ (differs from UK)J
11 inHK (differs from UK)K
12 inHHL (differs from UK)L
13 inJM (differs from UK)M
14 inJJN (differs from UK)N
15 inKO (differs from UK)O

Ladders from Wikipedia, "Bra size", cross-checked against A Bra That Fits' converter: we ran 18 measurement pairs through it in UK, US and EU labels on 25 September 2026, and our engine reproduces every answer (raw output in our repository).

Common conversions past DD

Where most UK-to-US mistakes happen.

UK sizes on other labelsComputed by the Bra Atlas engine.
UKUSEUFRAUJP
32E32DDD70F85F10EG70
34F34G75G90G12FH75
36FF36H80H95H14GI80
30G30I65I80I8Hno label
38GG38J85J100J16HHno label
32H32K70K85Kno labelno label

Three things converters get wrong

US "E" and "F" are not UK E and F

Many US brands skip DDD and print E for DD and F for DDD. On those labels a US 34E is a UK 34DD, one cup smaller than a UK 34E. Our converter reads a US E as DD and a US F as DDD, and tells you when it did. If the US brand's chart runs D, DD, DDD, E, trust the brand chart. Victoria's Secret prints both names ("DD (E)", "DDD (F)") and SKIMS skips DDD altogether: see brand size charts.

Australia drops FF

Australian bands are the UK band minus 22 (UK 34 is AU 12). Cups follow UK letters to F, but Berlei, the largest Australian brand, runs A to H with no FF or GG (Berlei size chart), and A Bra That Fits' Australian output does the same. So a UK 34FF is an AU 12G, and a UK 34G is an AU 12H.

Japanese cups run a letter ahead

Japan grades cups in 2.5 cm steps under JIS L 4006, so its letters run about one ahead of US and EU letters: a US 34D is roughly a Japanese E75 (OneMall, 2026). Converters disagree above DD by another letter, so we mark Japanese conversions as approximate.

Are UK and US bra sizes the same?

Bands are the same number in both. Cups share letters up to DD. After that the UK goes E, F, FF, G, GG, H and the US goes DDD, G, H, I, J, so a UK 34E is a US 34DDD and a UK 34FF is a US 34H.

What is a UK 34E in US sizes?

US 34DDD. Some US brands print it as 34F, because they label DD as E and DDD as F.

What is a US 34DDD in UK sizes?

UK 34E. In EU sizes it is 75F, in France 90F, in Australia 12E.

Sources

Each source was opened and checked on 25 September 2026. Where sources disagree, the page says so instead of picking one silently.

  1. Wikipedia, "Bra size": UK and US cup ladders, the +4 method, EN 13402 and JIS cup steps
  2. A Bra That Fits calculator (community calculator of r/ABraThatFits): we submitted 18 measurement pairs in 6 systems on 25 September 2026; raw output is in our repository
  3. Berlei Australia, size charts: AU band = underbust row, cups A to H with no FF or GG
  4. OneMall, "Japanese Bra Size Conversion" (11 September 2026): JIS cups in 2.5 cm steps; JP letter about one above the US letter