Bra Size Calculator
Find your true band size, cup fit, international sizes, sister sizes, and cup letter definitions.
Pull the tape snug against your ribcage directly beneath your breasts.
Measure around the fullest point of your chest while standing upright.
Visual Fit & Measurement Diagram
Recommended Primary Size (Modern Snug Fit)
32D
Sister Sizes (Equivalent Cup Volume)
Tighter Band
30DD
Looser Band
34C
Worldwide International Size Standards
US / Canada
32D
UK & South Asia (IN, BD, PK)
32D
Europe (EU / DE)
70D
France / Spain / North Africa
85D
Italy (IT)
2D
East Asia (Japan / Korea)
70E
China (CN)
70D
Australia / NZ
10D
Latin America (BR / MX)
40 / 32D
Cup Letter & Volume Guide (What does each letter mean?)
| Cup Letter | Bust - Underbust Difference | Typical Fit Description |
|---|---|---|
| AA | < 1.0 in (< 2.5 cm) | Very subtle projection / Petite cup |
| A | 1.0 in (~2.5 cm) | Small projection / Shallow profile |
| B | 2.0 in (~5.0 cm) | Moderate-small projection |
| C | 3.0 in (~7.5 cm) | Average / Medium balanced volume |
| D | 4.0 in (~10.0 cm) | Medium-full projection |
| DD / E | 5.0 in (~12.5 cm) | Full cup volume / Enhanced support |
| DDD / F | 6.0 in (~15.0 cm) | Deep projection / Generous cup capacity |
| G | 7.0 in (~17.5 cm) | Extra full volume / Reinforced band needs |
| H | 8.0 in (~20.0 cm) | Substantial projection |
| I | 9.0 in (~22.5 cm) | Plus-curve capacity |
| J | 10.0 in (~25.0 cm) | Deep full-bust profile |
| K | 11.0+ in (27.5+ cm) | Maximum bust volume |
South Asia (India, Bangladesh, Pakistan), the UK, and Commonwealth Africa use standard UK/US band numbers. East Asian (Japan/Korea) sizing uses 2.5cm cup intervals and typically runs 1 letter higher than Western cups.
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