Bra Band Size: Underbust Conversion Chart
Convert your underbust measurement to bra band sizes across US, UK, EU, and FR systems. Use our free converter and band size chart for a perfect fit.
Finding the correct bra band size starts with an accurate underbust measurement. The band provides about 80 percent of your bra support, so getting this number right is essential for comfort and fit. Use our bra band underbust converter to translate your measurement across US, UK, EU, and French sizing systems.
How to Measure Your Underbust Correctly
Stand upright and wrap a soft measuring tape directly under your bust, where the bra band would naturally sit. The tape should be level all around and snug against your skin. Exhale normally and take the measurement in inches or centimeters. This number is your raw underbust — the starting point for determining your band size in any regional system.
US and UK vs EU and FR Band Sizing
US and UK band sizes are based on inches and follow the same numbering: 30, 32, 34, 36, and so on. EU band sizes use centimeters and are numbered 65, 70, 75, 80, etc., representing the underbust circumference. French band sizes are similar to EU but typically add 15 to the number. Our underbust converter handles all four systems automatically.
Tips for a Better Band Fit
The band should sit horizontally across your back without riding up. You should be able to fit two fingers under the band comfortably. If the band rides up in the back, it is too loose — try the next hook tighter or go down a band size. For the complete picture including cup size, visit our full bra size converter.