Bra Size Calculator - Find Your Perfect Bra Size
Calculate your correct bra size using band and bust measurements with accurate US, UK, and EU size conversions
Bra Size Calculator
Your Bra Size
What is a Bra Size Calculator?
A Bra Size Calculator is a free tool that helps you determine your correct bra size by calculating the band size and cup size based on your body measurements. It provides accurate sizing in US, UK, and EU formats.
This calculator works for:
- First-time bra shopping - Find your starting size when buying your first bra
- Weight changes - Recalculate your size after gaining or losing weight
- Post-pregnancy - Determine new sizing after pregnancy and breastfeeding
- Online shopping - Get accurate measurements for ordering bras online
For calculating age-related body changes, check out our Age Calculator to track important life milestones and health checkpoints.
Planning a shopping budget for new clothing? Use our Monthly Budget Calculator to allocate funds for wardrobe updates and essentials.
Shopping during sales? Our Percent Off Calculator helps you calculate discounts and final prices for bra purchases.
How Bra Size Calculator Works
The calculation uses these formulas:
Where:
- Band Size = Measurement around ribcage under bust (rounded to nearest even number)
- Bust Measurement = Measurement around fullest part of bust
- Cup Size = Each inch difference equals one cup size (A, B, C, D, etc.)
Cup Size Chart: 1" = A, 2" = B, 3" = C, 4" = D, 5" = DD/E, 6" = DDD/F, 7" = G, 8" = H
Key Concepts Explained
Sister Sizes
Bras with same cup volume but different band/cup combinations (e.g., 34C = 32D = 36B).
Band Size
The number in your bra size represents the measurement around your ribcage.
How to Use This Calculator
Measure Band Size
Wrap tape snugly under bust, parallel to floor (e.g., 34 inches)
Measure Bust Size
Measure around fullest part of bust (e.g., 37 inches)
Enter Measurements
Input both measurements in inches or centimeters
Get Your Size
View your bra size in US, UK, and EU formats
Benefits of Using This Calculator
- • Accurate Sizing: Get precise measurements for better-fitting bras and improved comfort.
- • International Conversions: See your size in US, UK, and EU formats for global shopping.
- • Sister Sizes: Discover alternative sizes with the same cup volume for better fit options.
- • Online Shopping: Shop confidently online knowing your exact measurements and size.
Factors That Affect Your Results
1. Measurement Accuracy
Ensure tape is level and snug but not tight for most accurate results.
2. Body Changes
Weight fluctuations, pregnancy, and hormonal changes affect bra size.
3. Brand Variations
Different brands may fit differently even with the same size label.
Frequently Asked Questions (FAQ)
Q: How do I measure my bra size correctly?
A: Measure your band size by wrapping a measuring tape snugly around your ribcage directly under your bust. Round to the nearest whole number. Then measure your bust size at the fullest part of your bust. The difference between these measurements determines your cup size.
Q: What does the cup size letter mean?
A: Cup size is determined by the difference between your bust and band measurements. Each inch of difference represents one cup size: 1 inch = A cup, 2 inches = B cup, 3 inches = C cup, and so on. For example, if your band is 34 inches and bust is 37 inches, you're a 34C.
Q: How often should I measure my bra size?
A: You should measure your bra size every 6-12 months or whenever you experience weight changes, pregnancy, or notice your current bras don't fit properly. Body changes can affect your bra size significantly.
Q: Are bra sizes the same across all brands?
A: No, bra sizes can vary between brands and even between different styles from the same brand. This calculator provides standard US sizing, but always try on bras before purchasing and be prepared to adjust sizes between brands.