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34-Inch Underbust Bra Size

A snug 34″ underbust (86 cm) is a 34 band. Slide to your bust measurement and the size appears; the table shows every cup a 34 band can carry.

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My underbust is 34″: what's my size?

tape level, touching not compressing
Underbust 34″ · band 34 · your size
34C
Sister sizes
Read the guide →

The band comes from the underbust alone. 34″ → 34 band whatever your bust; the bust only decides the cup letter: one letter per inch above 34.

Lookup

Every size on a 34 band, by bust

BustDifferenceBra sizeSister sizes
35″ · 89 cm1″34A32B · —
36″ · 91 cm2″34B32C · 36A
37″ · 94 cm3″34C32D · 36B
38″ · 97 cm4″34D32DD · 36C
39″ · 99 cm5″34DD32DDD · 36D
40″ · 102 cm6″34DDD32G · 36DD
41″ · 104 cm7″34G32H · 36DDD
42″ · 107 cm8″34H32I · 36G
On the scale

Where 34″ lands

US band scale · your band and its sister bands
28303234363840424446
34″ → 34. Sister bands 32 and 36 hold the same cup volume with one cup letter up or down.
How a 34 band should feelLevel, firm on the loosest hook, two fingers underneath, no ride-up when you raise your arms
The band abroad

A 34 band in every system

US / UK34
EU / DE / JP75
FR / ES90
AU / NZ12
IT3
Underbust34″ · 86 cm

Odd number? No. 34 is the 34 band directly. Bands are always even; the underbust reading between them goes to the sister size that fits.

Measure

Getting the underbust right

1Snug and level

Firm against the ribs, level all the way round, on a normal exhale. A slack tape adds an inch and a band size.

2Round, don't add

Nearest whole inch, odd rounds up to even. Never add four inches: that is the outdated rule.

3Loosest hook when new

The band should fasten on the loosest hook and feel firm; move inward as it stretches over months.

Full technique with diagrams: how to measure your bra size.

Answered

34-inch underbust: answered

What band size is a 34 inch underbust?

A 34 band. Even readings are the band directly.

What bra size is a 34 inch underbust and a 37 inch bust?

34C: a three-inch difference on a 34 band. Bust 38 would be 34D, 36 would be 34B.

What is a 34 band in EU sizing?

EU 75 (US band × 2.5 − 10); FR 90; AU 12; IT 3.

Should the tape be tight for the underbust?

Snug: firm against the ribcage like a well-fitting band, not painful. Two inches of slack turns a 34 band into a 36.

Can a 34 inch underbust wear a 32 band?

Often, as a sister size. 32 with one cup letter up holds the same volume on a firmer band, useful if 34 rides up or you are between readings.

Shop itAt HauteFlair, our sister retailer

Opens HauteFlair’s own hub page; use your measured size there. 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.

Enter both measurements

Underbust and bust together give one exact size.

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