Free Bra Size Calculator Online
Calculate bra size from band and bust measurements with US, UK, EU, French, and Australian sizing conversions and sister size chart. — 100% free online utility, zero sign-up, zero paywalls, and private client-side processing.
How It Works
Measure Band Size
Measure snugly around ribcage directly under bust in inches or cm.
Measure Bust Size
Measure around the fullest part of bust.
View Calculated Size
Get band + cup size in US, UK, EU, French, and Australian systems.
Check Sister Sizes
View sister sizes (same cup volume, different band) for better fitting options.
Frequently Asked Questions
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