Bra Atlas

36DD sister sizes, conversions and measurements

36DD is where US "E" labels cause the most confusion: on brands that print E for DD it is sold as 36E, while a UK 36E is a full cup bigger.

Bra Atlas fitting card

36DDUK · same in the US

Measures about 36 in underbust and 41 in bust. Same cups as 34E and 38D.

UK
36DD
US
36DD
EU
80E
FR
95E
AU
14DD
JP
F80

Same cups 34E36DD38D

Every sister of 36DD

  • 30FFTighter band by 6 in, 3 cup letters up (US 30H, EU 65H)
  • 32FTighter band by 4 in, 2 cup letters up (US 32G, EU 70G)
  • 34ETighter band by 2 in, 1 cup letter up (US 34DDD, EU 75F)
  • 36DDThis size (US 36DD, EU 80E)
  • 38DLooser band by 2 in, 1 cup letter down (US 38D, EU 85D)
  • 40CLooser band by 4 in, 2 cup letters down (US 40C, EU 90C)
  • 42BLooser band by 6 in, 3 cup letters down (US 42B, EU 95B)

By Rai Ansar · Sizes computed by the Bra Atlas engine, sources checked · How this page was made

34E: band 34 in, same cup volume

34E

tighter band

36DD: band 36 in, same cup volume

36DD

your size

38D: band 38 in, same cup volume

38D

looser band

Same cups, three bands: 34E, 36DD, 38D hold the same cup volume.

Tape measurements that give 36DD

Computed by the Bra Atlas engine with the measured-band method, and checked by running each pair back through it.

Underbust and bust for 36DDA bust within about a quarter inch of the figure shown still gives 36DD.
Snug underbustFullest bustResult
35 in (89 cm)40.5 in (103 cm)36DD
35.5 in (90 cm)40.75 in (104 cm)36DD
36 in (91 cm)41 in (104 cm)36DD
36.5 in (93 cm)41.25 in (105 cm)36DD

Same body, other methods: 36 in and 41 in is a 40A with the traditional +4 method. With an odd 35 in underbust and a 40.5 in bust we print 36DD; calculator.net's rule (band rounded, cup from the raw difference) would print 36E. Why methods differ.

What is particular about 36DD

"36dd sister size" gets about 1,900 Google searches a month in the US and 110 in the UK (Google Ads data, September 2026).

Three calculators agreed

One of our 10 test measurements was a 36 in underbust with a 41 in bust. A Bra That Fits printed 36DD, calculator.net printed 36 DD/E, and our engine prints 36DD. The +4 method printed 40A.

US 36E is not UK 36E

Many US brands skip DDD and label DD as E and DDD as F, so a US "36E" is usually this size. A UK 36E is one cup bigger: US 36DDD. When a size page says E, check the brand's country.

Which sister to try

Band riding up: 34E (US 34DDD). Band digging in: 38D. 40C is two steps away, and its wires sit wider.

36DD in every system

36DD and its sisters on six labelsEach row holds the same cup volume.
UKUSEUFRAUJP (approx.)
30FF30H65H80H8GI65
32F32G70G85G10FH70
34E34DDD75F90F12EG75
36DD36DD80E95E14DDF80
38D38D85D100D16DE85
40C40C90C105C18CD90
42B42B95B110B20BC95

Other sizes and tools

Sources

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

  1. 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
  2. calculator.net, Bra Size Calculator: 10 measurement pairs run in a browser on 25 September 2026
  3. Wikipedia, "Bra size": UK and US cup ladders, the +4 method, EN 13402 and JIS cup steps