Bra Size Calculator: Japan

Measure once, and this calculator highlights your size in Japan's JP convention while showing all 7 international systems for imported brands. Enter your snug underbust and fullest bust below.

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Shopping for bras in Japan

Japanese sizing prints the cup before the band, C75 rather than 75C, and its cup letters run roughly one letter fuller than EU for the same measurements: many EU B wearers buy a JP C. Bands run 65 to 90 in most ranges, and everything above that gets scarce quickly.

Japanese brands like Wacoal Japan and Peach John cut for shorter torsos and closer-set shapes, with beautifully engineered smaller bands that are hard to find anywhere else.

Brands you will commonly see: Wacoal, Peach John, Triumph Japan, Uniqlo.

How Japan writes a bra size

Bands in Japan are centimetres rounded to fives, matching the European convention, and ranges thin out quickly above 90.

Cup letters run about one place fuller than European for the same measurements, so a great many EU B wearers buy a Japan C.

Japan prints the cup before the band: C75, not 75C.

JP size conversion chart

Every row is one body. The JP column is what the label prints; the others are what the same bra is called elsewhere, which is what you need when a brand ships from abroad.

JP	US	UK	EU	FR
C70	32B	32B	70B	85B
E70	32D	32D	70D	85D
C75	34B	34B	75B	90B
D75	34C	34C	75C	90C
E75	34D	34D	75D	90D
F75	34DD	34DD	75E	90E
D80	36C	36C	80C	95C
E80	36D	36D	80D	95D
F80	36DD	36DD	80E	95E
G80	36DDD	36E	80F	95F
E85	38D	38D	85D	100D
F85	38DD	38DD	85E	100E
E90	40D	40D	90D	105D

Common Japan conversions, answered

What is a US 34D in Japan?

A US 34D is a E75 in Japan. The same bra is a UK 34D and an EU 75D.

What is a US 34DD in Japan?

A US 34DD is a F75 in Japan. The same bra is a UK 34DD and an EU 75E.

What is a US 36DD in Japan?

A US 36DD is a F80 in Japan. The same bra is a UK 36DD and an EU 80E.

What is a US 36DDD in Japan?

A US 36DDD is a G80 in Japan. The same bra is a UK 36E and an EU 80F.

Look up a specific size

32D 32DD 32DDD 32F 32I 32K 34D 34DD

28 band 30 band 32 band 34 band 36 band 38 band 40 band 42 band

Frequently asked questions

What bra sizing system does Japan use?

Japan primarily uses JP sizing conventions in mainstream retail, though imported brands can carry other systems' labels. The calculator above highlights your JP size and shows all 7 systems for imports.

Which bra brands are common in Japan?

Commonly available names include Wacoal, Peach John, Triumph Japan, Uniqlo. Local availability shifts, and each brand's own centimeter chart beats any converted label when they disagree.

What is a US 34DD in Japan sizing?

A US 34DD is a F75 in Japan. The same bra is a UK 34DD and an EU 75E, because the cup ladders diverge after D.

Do I add inches to my underbust measurement in Japan?

No. The old habit of adding four or five inches was written for non-stretch fabric and produces a band about two sizes too loose on a modern elastic one. Measure snug and level, and use that number directly, whichever system the label uses.

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Last updated August 2026.