Bra Size Calculator
Find your correct bra size in US, UK, EU, and other international sizing systems.
Bra Size Calculator
Find your correct bra size in US, UK, EU, and other international sizing systems.
Unit Conversion
ℹ️ All units normalised to a common base before converting to ensure accuracy
Disclaimer
Results provided by this calculator are for informational and educational purposes only. They are based on the values you enter and standard formulas, and should not be considered financial, medical, legal, or professional advice. Always consult a qualified professional before making important decisions based on these results. Roughtools makes no warranties regarding the accuracy or completeness of these calculations for your specific situation.
Frequently Asked Questions
Pro Tips
Always double-check your unit conversion direction — dividing when you should multiply (or vice versa) produces a result off by the conversion factor squared.
For temperature conversions, remember the formulas differ: Celsius to Fahrenheit = (C × 9/5) + 32. Fahrenheit to Celsius = (F − 32) × 5/9. Kelvin = Celsius + 273.15.
Imperial units have multiple definitions (fluid ounce vs weight ounce, US vs UK gallon). Always confirm which system applies — especially for cooking or scientific work.
Significant figures matter in scientific conversions. If your input has 2 significant figures, don't report 6 decimal places of precision — it implies false accuracy.
When to Use This Calculator
Convert between metric and imperial units for temperature, distances, weights, and speeds when travelling abroad.
Convert between US and metric measurements for international recipes or ingredient scaling.
Convert units for scientific calculations where SI units are required.
Convert between measurement systems when working with international suppliers or standards.
Convert units to compare product sizes and prices across different packaging formats.
About the Bra Size Calculator
This bra size calculator determines your correct bra size across multiple international sizing standards — US, UK, EU/European, French, Italian, and Australian — from two simple measurements: underbust (band) circumference and bust circumference. Enter both measurements in inches or centimeters to see your size in all systems simultaneously, including half-cup sizes where available. Note that bra sizing varies by brand — use this as a starting point and try multiple sizes when shopping.
How to Use the Bra Size Calculator
- 1
Measure your underbust circumference snugly in inches or cm (just below the breast).
- 2
Measure your bust circumference at the fullest point (not too tight).
- 3
Enter both measurements and select your unit.
- 4
See your bra size in US, UK, EU, French, Italian, and Australian standards.
- 5
If between sizes, try both — many women find sister sizes (same cup volume, different band) fit better.
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