Bra Size Calculator
Compute US bra size from band and bust measurements, with US ↔ UK ↔ EU conversion table.
Result
- US (band + cup)32D
- UK (band + cup)32D
- EU (band cm + cup)70D
- Band measurement (in)32.00 in
- Bust measurement (in)36.00 in
- Cup difference (bust − band)4 in
- US band size roundingnearest even ≥ band → 32
- EU band conversion32" × 2.54 − 10 = 71.3 cm → 70 cm
Step-by-step
- Cup difference = bust − band = 36.00 − 32.00 ≈ 4 in (each inch = one cup size).
- Round band UP to nearest EVEN inch: 32.
- US cup letter index 4 → D; UK index → D.
- EU band: ~32" in cm − 10 cm shrink convention → 70 cm.
How to use this calculator
- Measure your underbust (band) snugly with the tape level.
- Measure your full bust at the fullest point, with the tape level and not pulled tight.
- Enter both numbers in inches or centimetres.
- The US size + UK + EU equivalents appear together.
- If two sister sizes are close, try both — a 34C and a 32D have the same cup volume but different band tension.
About this calculator
Bra sizing across the US, UK, and EU uses the same two underlying measurements (band and bust circumference) but reports cup letters and band numbers differently. The cup difference (bust minus band, in inches) maps to a letter — 1"=A, 2"=B, 3"=C, 4"=D — but the system diverges past D: the US uses DD, DDD, G, H, …; the UK uses DD, E, F, FF, G, GG, …. The band measurement is rounded up to the nearest even inch in the US and UK; the EU uses centimetres in increments of 5 (60, 65, 70, 75, 80…). This calculator applies the modern "no +4/+5 inches" rule recommended by Bratabase, Linda the Bra Lady, and most professional fitters — the older "add 4-5 inches to your underbust measurement" method consistently undersizes bands.