European Bra Size Calculator
Enter your measurements to get an estimated EU bra size (for example: 75C, 80D, 70E).
This tool gives a starting size. Final fit may vary by brand, bra style, and breast shape.
How European bra sizing works
European bra sizes usually follow a two-part format: a band number (such as 70, 75, 80) and a cup letter (A, B, C, D, E, and beyond). The band reflects your ribcage measurement, while the cup reflects the difference between bust and underbust measurements.
Unlike many older fitting systems, modern EU fitting usually does not add extra inches to the band. Instead, your underbust measurement is rounded to the nearest available EU band size (typically in 5 cm steps).
How to measure for best results
1) Measure your underbust
Use a soft measuring tape around your ribcage, directly under your bust. Keep it snug but not painfully tight, and make sure it sits level all the way around.
2) Measure your full bust
Wrap the tape around the fullest part of your chest, usually across the nipples. Keep the tape level and comfortable. If possible, measure while wearing a non-padded bra for more consistent results.
3) Use the difference to estimate cup size
The calculator subtracts underbust from full bust. That difference (in centimeters) maps to a cup letter.
| Bust - Underbust Difference (cm) | Estimated EU Cup |
|---|---|
| Less than 10 | AA |
| 10 to < 12 | A |
| 12 to < 14 | B |
| 14 to < 16 | C |
| 16 to < 18 | D |
| 18 to < 20 | E |
| 20 to < 22 | F |
| 22 to < 24 | G |
| 24 to < 26 | H |
| 26 to < 28 | I |
| 28 to < 30 | J |
| 30 to < 32 | K |
| 32+ | L+ |
Understanding sister sizes
If a band feels too tight but the cup feels right, you can try a sister size: go up one band and down one cup. If the band is too loose, do the opposite.
- Example: 75C sister sizes are often 70D and 80B.
- Use sister sizes when only one part of the fit is off.
- Always re-check strap and wire comfort after switching size.
Signs your bra size may need adjustment
- Band rides up your back (usually too loose).
- Cups wrinkle or gape (often too big cup or wrong shape).
- Spillage at top or sides (often too small cup).
- Underwire sits on breast tissue (cup likely too small or wrong wire width).
- Straps dig in deeply (band may be too loose, forcing straps to carry too much weight).
EU vs UK/US sizing: quick note
Brands may label sizes differently depending on region. A bra sold in Europe may show an EU size and a converted UK/US size on the same tag. Always check the brand’s own chart if you are ordering online.
FAQ
Why does this result differ from my current bra?
Many people wear bands that are too loose and cups that are too small. Also, size labels are not perfectly standardized across all brands.
Is this calculator accurate?
It is accurate as a starting estimate. Final fit still depends on bra construction (balconette, plunge, full cup, sports) and your natural shape.
What if I am between two sizes?
Try both. If comfort is close, keep the one with better band support and wire placement. For everyday wear, comfort and stability should come before letter perfection.
Final tip
Use this EU bra size calculator to narrow your choices, then test at least two nearby sizes in the same bra model. A quick fit check in front of a mirror can save time, money, and discomfort.