Bra Size Calculators by Country

Bra sizing is not universal: the US, UK, EU and other systems number their bands differently and — above a DD cup — spell their cup letters differently too. Pick your country below for a calculator preset to the sizing system its brands actually use, with a local size chart and conversion notes.

Choose your country

United StatesUS sizing – inch bands, DDD cups — Example: 34C United KingdomUK sizing – inch bands, E/F/FF cups — Example: 34E AustraliaAUS sizing – bands 6–26, UK-style cups — Example: 12C CanadaShops mostly in US sizing — Example: 34C Europe (EU)EU sizing – cm bands 60–110 — Example: 75D New ZealandNZ sizing – bands 6–26, UK-style cups — Example: 12C IndiaIN sizing – inch bands, UK-style cups — Example: 34C JapanJP sizing – cm bands 60–110 — Example: 75D

How international bra sizing works

Every system has the same two parts — a band number and a cup letter — but the numbers and letters are counted differently:

  • Inch-band systems (US, UK, IN): bands are even numbers in inches (28, 30, 32…). Cup letters match across US/UK/IN through DD, then diverge: US goes DD → DDD → G while UK/IN go DD → E → F.
  • Centimetre-band systems (EU, JP): bands are your underbust in centimetres, rounded to the nearest 5 (65, 70, 75…). A 30-inch underbust (about 76 cm) is a 75 band; a 34-inch underbust (about 86 cm) is an 85.
  • Australia & New Zealand: bands are the inch band minus 22 (so a US/UK 34 is an AUS/NZ 12), with UK-style cup letters.
  • Canada: most Canadian retailers label in US sizing, so the Canada calculator uses the US system.

The practical rule: convert the whole size from your measurements, not by swapping letters. A US 34DDD is a UK 34E — the number and the letter both move between systems, and some systems start counting cups from a different letter. And because brands grade differently, treat every conversion as a starting point and check the brand’s own chart.

Frequently Asked Questions

Which country’s sizing should I use?

Use the sizing printed on the bras you buy most. Shopping US brands? Use the US calculator. UK high-street labels? Use the UK one. When a retailer lists multiple systems, match the one on its size chart — not the one you wish it used.

Is a 34C the same everywhere?

Through a C cup, mostly yes across US, UK and IN sizing (same inch band, same letter) — a 34-inch underbust and 37-inch bust read 34C in all three. But the same measurements read 85E in EU and JP sizing and 12C in AUS/NZ sizing: same body, different labels. Above DD the letters diverge further.

Why does the EU use such different band numbers?

EU bands are based on centimetres rather than inches: your underbust in centimetres, rounded to the nearest 5. A 30-inch underbust (about 76 cm) is a 75 band; 34 inches (about 86 cm) is an 85. The cup letters then follow their own A–H progression, counted from A.

Do I need a different calculator for each country?

Not strictly — the main calculator covers all seven systems in one dropdown. The country pages exist so each system gets its own chart, conversion table and FAQs without clutter.

Are conversions between systems exact?

No. They are the closest standard equivalents, but brands grade patterns differently and some invent their own letters. Treat conversions as a strong starting point and try the size on.