Bra Size Calculator
Calculate your bra size with international conversions and sister size recommendations for the perfect fit
Bra Size Calculator
Measure around your ribcage, just under your bust, snug but not tight
Measure around the fullest part of your bust, keeping the tape level
Your Calculated Bra Size
38D
US Sizing
Band Size
38
Cup Size
D
Sister Sizes (Alternative Fits)
40C
36DD/E
Sister sizes offer similar cup volume with different band fits. Try these if your calculated size feels too tight or loose in the band.
International Size Conversions
United States
38D
United Kingdom
38D
European Union
63D
France
78D
Italy
5D
Australia
8D
How to Measure Correctly
Band Measurement
- • Measure directly under your bust
- • Keep tape parallel to the floor
- • Tape should be snug but not tight
- • Breathe normally while measuring
- • Round to nearest half inch/cm
Bust Measurement
- • Measure around fullest part of bust
- • Wear a non-padded, well-fitting bra
- • Keep tape level and not too tight
- • Don't compress your bust
- • Take measurement from the side view
Bra Fit Tips
Signs of Good Fit
- • Band lies flat against your back
- • Cups contain breast tissue completely
- • Center gore lies flat against sternum
- • Straps don't dig into shoulders
- • No spillage over cups
When to Get Professionally Fitted
- • After significant weight change
- • During/after pregnancy
- • If you haven't been fitted in 2+ years
- • If your current bras don't fit well
- • For special occasion or sports bras
What is Bra Size Calculator?
A bra size calculator helps determine your correct bra size using standard measurements and converts between international sizing systems. Proper bra fit is important for comfort, health, and confidence.
Why Correct Bra Size Matters
- Comfort: Proper fit prevents discomfort, chafing, and pain
- Support: Correct sizing provides better breast support and posture
- Health: Poor fit can cause back pain and skin irritation
- Appearance: Well-fitting bras enhance your silhouette and clothing fit
International Sizing Systems
- US/Canada: Uses inches for band, letter progression for cups
- UK: Similar to US but different cup progression after D
- European: Uses centimeters for band sizes
- French: Similar to EU but with different band numbering
- Italian: Uses numbered system for bands
FAQ - Bra Size Calculator
It's recommended to measure your bra size every 6-12 months, as your body can change due to weight fluctuations, hormones, age, and other factors. Also remeasure after significant life events like pregnancy, weight loss/gain, or major health changes.