Bra Size Calculator
- Updated
- Imperial and metric
- Free, no sign-up
Results
Estimated bra size: US 32D, UK 32D, EU 70D.
| US | UK | EU | FR / ES / BE | AU / NZ | |
|---|---|---|---|---|---|
| Smaller band, bigger cup | 28DDD/F | 28E | 60F | 75F | 6E |
| Smaller band, bigger cup | 30DD | 30DD | 65E | 80E | 8DD |
| Your size | 32D | 32D | 70D | 85D | 10D |
| Bigger band, smaller cup | 34C | 34C | 75C | 90C | 12C |
| Bigger band, smaller cup | 36B | 36B | 80B | 95B | 14B |
Brand sizing varies, and the same size can fit differently between styles, so treat this as a starting point. A professional fitting is the most reliable way to find your size.
How to use the bra size calculator
- Wear a lightly padded or unpadded bra that fits reasonably well, and use a soft tape measure. Keep the tape level all the way around.
- Measure the under-bust snugly around the rib cage, directly below the bust, after breathing out.
- Measure the bust loosely around the fullest part, without compressing it.
- Enter both in inches or centimeters. If the under-bust rounds to an odd number, choose whether the band should round up or down.
Bra size method
Cup steps = bust − band (in), rounded to the nearest inch
0 = AA · 1 = A · 2 = B · 3 = C · 4 = D · 5 = DD (UK, US) or E (EU) …
EU band = 2.5 × band − 10 · FR / ES / BE = EU + 15 · AU / NZ = band − 22
This is a common tape-measure method: the band number comes straight from the under-bust, and every inch (2.54 cm) the bust exceeds the band adds a cup size. Older methods added 4 or 5 inches to the under-bust, which is why some charts give a larger band and a smaller cup for the same measurements. Other countries' sizes are converted with the label equivalents that international brands print on the same bra. Centimeter measurements are converted to inches first.
Worked example
An under-bust of 31.5 in rounds to 32, which is already even, so the band is 32. The bust is 36 in: 36 − 32 = 4 inches, four cup steps, a D cup. The estimated size is US 32D, which is UK 32D, EU 70D, France 85D and Australia 10D. Its nearest sister sizes are 28DDD/F, 30DD, 34C, 36B.
With an under-bust of 33 in and a bust of 37 in, the odd band can go either way: rounding up gives 34C, rounding down gives a firmer 32DD. Trying both is worthwhile.
Band size conversion
| US / UK | EU | France, Spain, Belgium | Australia, New Zealand |
|---|---|---|---|
| 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 |
| 46 | 105 | 120 | 24 |
Cup size conversion
| Bust − band | US | UK, AU / NZ | EU, FR / ES / BE |
|---|---|---|---|
| 0 in (0.0 cm) | AA | AA | AA |
| 1 in (2.5 cm) | A | A | A |
| 2 in (5.1 cm) | B | B | B |
| 3 in (7.6 cm) | C | C | C |
| 4 in (10.2 cm) | D | D | D |
| 5 in (12.7 cm) | DD | DD | E |
| 6 in (15.2 cm) | DDD/F | E | F |
| 7 in (17.8 cm) | G | F | G |
| 8 in (20.3 cm) | H | FF | H |
| 9 in (22.9 cm) | I | G | I |
| 10 in (25.4 cm) | J | GG | J |
| 11 in (27.9 cm) | K | H | K |
| 12 in (30.5 cm) | L | HH | L |
| 13 in (33.0 cm) | M | J | M |
US brands differ most above a D: some use DD, DDD and then G, others DD, E, F. UK and Australian brands double letters (DD, FF, GG); European brands go straight through the alphabet.
Sister sizes
A cup letter only means something on a particular band: a 32D and a 34C hold about the same volume. If a band feels too loose or too tight, move one band size and the opposite way by one cup. For 32D, that means 28DDD/F, 30DD, 34C, 36B.
Fit tips
- The band does the supporting. It should sit level and snug on the loosest hook when new, so you can tighten it as it stretches.
- Check the cups. Gaping suggests a smaller cup or a different style; spilling over or a center that doesn't lie flat suggests a larger cup.
- Sizes vary by brand and style. Treat the result as a starting point and try a size either side. A professional fitting is the most reliable way to find your size.
- Remeasure from time to time. Weight changes, pregnancy, exercise and age all change measurements.
For shoes, the shoe size conversion chart converts between US, UK, EU, Japanese and Mondopoint sizes from your foot length.
Frequently asked questions
How do I calculate my bra size?
Round your under-bust in inches to an even number for the band, then subtract the band from your bust: each inch is one cup size (1 = A, 2 = B, 3 = C, 4 = D, 5 = DD). An under-bust of 31.5 in and a bust of 36 in gives a 32 band and a 4-inch difference: 32D.
What is a 32D in UK, EU and Australian sizes?
Using the label equivalents most brands print, US 32D is UK 32D, EU 70D, France, Spain and Belgium 85D, and Australia and New Zealand 10D. Above a D the letters change: US DD is UK DD and EU E, and US DDD/F is UK E and EU F.
What are sister sizes?
Sizes with about the same cup volume on a different band. Going up one band size means going down one cup: the sister sizes of 34C are 32D and 36B, then 30DD and 38A. Try a sister size when the cups fit but the band doesn’t.
Should I round my band size up or down?
Bands come in even numbers, so an odd under-bust has to go one way. Rounding up gives a looser band, rounding down a firmer one. With a 33 in under-bust and a 37 in bust, rounding up gives 34C and rounding down 32DD, so it is worth trying both.
Why does my size differ between brands?
There is no single international standard for bra sizes. Brands use their own patterns, stretch and cup shapes, and some charts still add 4 inches to the under-bust. Use the calculator as a starting point; a professional fitting is the most reliable guide.