G90 Bra Size, In Full
A Japanese G90 is a 90 cm band with a G cup: written cup-first, measured in 2.5 cm steps, and one letter ahead of the Western alphabet. In US terms this body wears a 40DDD.
G90 measurements
A Japanese G is not a Western G
Japanese cup labels start earlier and step in 2.5 cm increments, so each letter sits roughly one label ahead of its Western namesake: this G90 corresponds to a US 40DDD and EU 90F. Order your Japanese letter from a Western shop (or vice versa) and you’re a full cup off before the parcel ships. The converter translates in both directions.
Bands translate cleanly (same centimeters as EU labels); only the letters shift.
G90 sister sizes
Japanese sisters move in 5 cm band steps with one cup letter, same volume, different circumference. Useful when domestic stock stops one band short of yours.
What works at this size
At this depth Japanese domestic stock is genuinely scarce: this is specialist territory, and the practical route is international full-bust brands bought by conversion. The US/UK columns below are the sizes to shop.
G90: answered
What is Japanese G90 in US sizing?
US 40DDD (UK 40E). Japanese cup letters sit one label ahead of Western ones for the same body (a Japanese G corresponds to a Western F-tier cup) so carrying the letter across unconverted buys a cup too big.
What measurements is G90 for?
An underbust around 90 cm (roughly 87.5–92.5 cm) and a top bust near 115 cm: a difference of about 25 cm, which Japanese sizing labels G. Japan measures in 2.5 cm cup steps against Europe's 2 cm, so conversions are nearest-label, not exact.
Why is the cup letter written first in G90?
Japanese convention writes cup-then-band. C70, not 70C. Same information, reversed order; on tags in Japan you may also see the band alone (70) with the cup on a separate line.
HauteFlair labels cups in UK letters, so these links already convert your size by position (a US DDD lands on a UK E, a US G on a UK F). HauteFlair is owned by the same company as Brasize.ai; that relationship never changes the sizing math, charts, or fit advice on this page. How this site makes money.
Start from the measured size
Two measurements, no inches added, sister sizes attached.
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