Bra Size Calculator
Enter your measurements to find your band and cup size, with international conversions.
Uses the standard difference method. Brands vary a lot — treat this as a starting point and try sister sizes if the fit is off.
Band size conversion
| US/UK | EU | FR/ES | AU/NZ |
|---|---|---|---|
| 28 | 60 | 75 | 6 |
| 30 | 65 | 80 | 8 |
| 32 | 70 | 85 | 10 |
| 34 | 75 | 90 | 12 |
| 36 | 80 | 95 | 14 |
| 38 | 85 | 100 | 16 |
| 40 | 90 | 105 | 18 |
| 42 | 95 | 110 | 20 |
| 44 | 100 | 115 | 22 |
Cup size conversion
| Bust − band | US | UK | EU |
|---|---|---|---|
| 0" | AA | AA | AA |
| 1" | A | A | A |
| 2" | B | B | B |
| 3" | C | C | C |
| 4" | D | D | D |
| 5" | DD | DD | E |
| 6" | DDD/F | E | F |
| 7" | G | F | G |
| 8" | H | FF | H |
| 9" | I | G | I |
FAQ
How do I measure my bra size?
Measure your underbust (snugly, just under your bust) for the band, and your bust (across the fullest part) for the cup. Enter both above. Wear an unpadded bra or no bra for accuracy.
How is cup size calculated?
Cup size is the difference between your bust and band measurements: about 1 inch = A, 2 = B, 3 = C, 4 = D, 5 = DD, and so on.
How do US, UK and EU bra sizes differ?
Bands convert by measurement (US 34 = EU 75 = UK 34). Cups diverge above D: US DD = UK DD = EU E; US DDD/F = UK E = EU F. See the charts below.
What are sister sizes?
If the band feels off, you can go up a band and down a cup (or vice versa) for the same cup volume — e.g. 34C ≈ 32D ≈ 36B.