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65A bra size

A 65A bra is cut for an underbust of 62.5–67.5 cm and a bust of 77–79 cm. Below it is the same size as every other system prints it, and the sister sizes that hold the same cup.

65A in every system

EU
65A
RU
65A
US
30A
UK
30A
FR
80A
JP
65A

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 62.5–67.5 cm all round to 65. The cup is how far the bust exceeds that band’s nominal value: 12–14 cm gives this letter, at two centimeters per letter starting at ten. Add them and you get a bust of 77–79 cm.

The cup is measured against the nominal 65, 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, 65A is an underbust of 24.6–26.6" and a bust of 30.3–31.1". Note that the UK and US band number is not that measurement: 65 cm is 24.6–26.6", and the band is called 30A because the English notation adds four inches.

Same cup as 65A, different band

One band up is one letter down, because the cup is measured over the band — which makes 60B, 70AA the same volume as 65A. 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

65AA, 65B, 60A, 70A — a letter either side of 65A on this band, and this letter on the neighbouring bands.