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110D bra size

A 110D bra is cut for an underbust of 107.5–112.5 cm and a bust of 128–130 cm. Below it is the same size as every other system prints it, and the sister sizes that hold the same cup.

110D in every system

EU
110D
RU
110D
US
48D
UK
48D
FR
125D
IT
9D
JP
110D

Where each notation comes from

What each notation means — why the British band reads 34 and the Italian reads 2 — is set out system by system on the bra size page.

Sources

Nothing here is looked up in a table of equivalents: band and cup are computed once from the metric ladder, then printed in each system’s own letters (formula version 2).

  • en.wikipedia.org the underbust ladder in 5 cm steps and the AA–H cup table
  • en.wikipedia.org the British and American cup runs, the French +15 shift, the Italian numbering
  • en.wikipedia.org the "+0" and "+4" methods, sister sizes, measuring upright and leaning forward
  • ru.wikipedia.org the Russian table: the same intervals, the same letters

Checked: no date on record

Where these numbers come from

The band is the underbust rounded to the nearest five centimeters, so 107.5–112.5 cm all round to 110. The cup is how far the bust exceeds that band’s nominal value: 18–20 cm gives this letter, at two centimeters per letter starting at ten. Add them and you get a bust of 128–130 cm.

The cup is measured against the nominal 110, not against the tape. That is what every published chart does, and it is why an underbust at the bottom of this band and one at the top get the same letter despite five centimeters between them. Near a band edge, try the sister size too.

In inches, 110D is an underbust of 42.3–44.3" and a bust of 50.4–51.2". Note that the UK and US band number is not that measurement: 110 cm is 42.3–44.3", and the band is called 48D because the English notation adds four inches.

Same cup as 110D, different band

One band up is one letter down, because the cup is measured over the band — which makes 105E, 115C the same volume as 110D. In a shop the printed size that fits is routinely not the one the tape said, so these are worth trying on.

One step away

110C, 110E, 105D, 115D — a letter either side of 110D on this band, and this letter on the neighbouring bands.