AI Bra Size Calculator
Get accurate measurements with our advanced AI fitting technology
Your Perfect Fit
Enter your measurements to calculate your accurate bra size with our AI-powered fitting system.
How to Calculate Your Bra Size Accurately
Finding your correct bra size is essential for comfort and support. You only need two measurements: your band size and your bust size. For the best results, measure without a bra or while wearing a non-padded one. Keep the measuring tape level and snug.
Pro Tip: Always measure yourself every 6-12 months, as your body can change.
Step 1: Find Your Band Size
- Wrap a soft tape measure around your ribcage, just under your bust.
- Ensure the tape is parallel to the floor.
- Exhale to get a snug measurement. Round to the nearest whole inch.
- Add inches to this number:
- If the number is even, add 4 inches.
- If the number is odd, add 5 inches.
This final number is your band size.
Step 2: Measure Your Bust Size
- Wrap the tape around the fullest part of your bust.
- Keep the tape straight across your back. Do not pull it too tight.
- Round this measurement to the nearest whole inch.
Step 3: Calculate Your Cup Size
Now, find the difference between your bust size and your band size.
- Subtract your band size from your bust size.
- The difference in inches determines your cup letter.
Use this standard cup size chart:
| Difference (inches) | US Cup Size |
|---|---|
| 1″ | A |
| 2″ | B |
| 3″ | C |
| 4″ | D |
| 5″ | DD/E |
| 6″ | DDD/F |
Step 4: Find Your Full Bra Size
Combine your band size number and cup letter. This is your bra size.
Example:
- Underbust: 32 inches (even) -> 32 + 4 = 36 band
- Bust: 39 inches
- Difference: 39 – 36 = 3 inches -> C cup
- Your Bra Size: 36C
Important Bra Fitting Tips
A good fit makes all the difference. Keep these tips in mind.
- Band Provides Support: The band should be snug and level. It should not ride up.
- Sizing Varies: Not all brands fit the same. Use your size as a starting point for trying on bras. For more on this, see our guide to bra fitting issues.
- Try Sister Sizes: If the band fits but the cup doesn’t, try a “sister size.” For example, a 34C could also try a 32D or a 36B.
When to Remeasure Yourself
Your body changes over time. You should recalculate your size after significant weight change, pregnancy, or surgery. Regular measurements ensure you always have the right support.
For a visual guide, many brands like Victoria’s Secret offer online fitting tools.
Example: If your band size is 36 and your bust measurement is 38 inches, the difference is 2 inches.
Find Your Cup Size using this Difference:
- 0-inch difference = AA
- 1-inch difference = A
- 2-inch difference = B
- 3-inch difference = C
- 4-inch difference = D
- 5-inch difference = DD (or E)
- 6-inch difference = DDD (or F)
- …and so on! Each additional inch adds another cup size.
Example: If your band size is 36 and your bust measurement is 38 inches, the difference is 2 inches, which equals a B cup. Your initial bra size would be 36B.
Finding Your Perfect Fit: Beyond the Numbers
While our online bra calculator provides a fantastic starting point, remember that bra sizes can vary slightly between brands and styles. Think of your calculated size as your accurate foundation, not a rigid rule.
A truly well-fitting bra should:
The Band: Feel snug and parallel to the floor around your back. You should only be able to fit two fingers comfortably under the band. It shouldn’t ride up your back.
The Cups: Enclose your entire breast tissue without any gaping or spilling over the top or sides.
The Straps: Provide minimal support; the band does most of the work! They shouldn’t dig into your shoulders.
The Center Gore: The piece of fabric between the cups should lie flat against your sternum.
Don’t be afraid to try on a few sizes around your calculated one (e.g., if you’re a 34C, also try a 32D or a 36B – called “sister sizes”). This will help you find the absolute best fit for your unique shape. Consult a bra size chart if you want to explore sister sizes further.
Step Into Comfort and Confidence!
Finding your accurate bra size is a game-changer. It’s about more than just looking good; it’s about comfort, support, and feeling confident in your own skin. Use this bra measurement guide as your secret weapon to banish ill-fitting bras forever.
Disclaimer: While this guide provides an excellent way to determine your size at home, nothing beats the expertise of a professional bra fitter. For the most personalized recommendations and to explore different styles, we always recommend visiting a lingerie specialist for a professional bra fitting. They can offer expert advice and ensure you get the absolute best fit for your unique body.