Bra Size Calculator
Find your perfect fit – US, UK & EU sizing
Your Bra Size
—
Size Conversion
ℹ️ This calculator provides estimates based on standard sizing. For best fit, always try bras on or consult a professional fitter.
How to measure
- Underbust: Measure snugly around your ribcage, just below your bust.
- Overbust: Measure loosely around the fullest part of your bust.
- Band size is the underbust measurement rounded to nearest even number.
- Cup size = difference between overbust and underbust (1 inch = 1 cup size).
All calculations are instant and local – no data leaves your device.
Fitting Guide
📏 How to Measure Correctly
- Use a soft measuring tape, not metal.
- Measure underbust snugly (exhale normally).
- Measure overbust loosely across the fullest part.
- Take measurements while wearing a non-padded bra.
💡 Signs of a Poor Fit
- Band rides up in back → too loose.
- Breasts spilling over cups → cup too small.
- Gaping at top of cups → cup too large.
- Straps digging in → need adjustment or different style.
📊 Cup Size Difference Chart (Inches)
| Diff (in) | US/UK Cup | EU Cup |
|---|---|---|
| <1 | AA | AA |
| 1 | A | A |
| 2 | B | B |
| 3 | C | C |
| 4 | D | D |
| 5 | DD/E | E |
| 6 | DDD/F | F |
| 7 | G | G |
| 8 | H | H |
| 9 | I | I |
| 10 | J | J |
🌍 Band Size Equivalents
| US/UK | EU (cm) | FR/ES |
|---|---|---|
| 28 | 60 | 75 |
| 30 | 65 | 80 |
| 32 | 70 | 85 |
| 34 | 75 | 90 |
| 36 | 80 | 95 |
| 38 | 85 | 100 |
| 40 | 90 | 105 |
| 42 | 95 | 110 |
Bra Size Calculator
A Bra Size Calculator helps you figure out your bra size using simple body measurements like band size and bust size. Wearing the bra size is important for comfort, support, posture and confidence. Many people wear the bra size without realizing it which can cause discomfort poor fitting shoulder pressure, back pain or an uneven appearance under clothes.
The UseToolsPro Bra Size Calculator makes it easy to find an estimated bra size. You just need to enter your measurements. The calculator will help you understand your possible band size, cup size and overall bra size.
What is a Bra Size?
A bra size usually has two parts: the band size and the cup size.
. The band size is the measurement around your ribcage under the bust. It represents the number part of the bra size, such as 32, 34 36 or 38.
. The cup size is based on the difference between your bust measurement and band measurement. It represents the letter part of the bra size, such as A, B, C, D or DD.
For example in 34B 34 is the band size and B is the cup size.
Why Bra Size Matters
Wearing the bra size can make a big difference in daily comfort and appearance. A fitted bra provides better support improves clothing fit and reduces unnecessary pressure on the shoulders and back.
A wrong bra size may cause:
. Loose or tight band fitting
. Cup gaps or overflow
. Shoulder strap marks
. discomfort
. Poor support
. Uncomfortable movement
. Uneven shape under clothes
That is why checking your bra size regularly can be helpful.
How to Use the Bra Size Calculator
Here are the steps:
> Step 1
Measure around your ribcage directly under your bust. This is your band measurement.
> Step 2
Measure around the part of your bust. Keep the measuring tape straight and comfortable.
> Step 3
Enter both measurements into the calculator.
> Step 4
Select your measurement unit if available.
> Step 5
Click the Calculate button.
> Step 6
View your estimated bra size instantly.
How to Measure Correctly
. Use a measuring tape.
. Stand straight in a position.
. Do not pull the tape tightly.
. Keep the tape level around your body.
. Measure while wearing a -padded bra for better accuracy.
. Take measurements in inches or centimeters depending on the calculator option.
Benefits of Using UseToolsPro Bra Size Calculator
.. Easy to use
. No registration required
. Works on mobile and desktop
. Helps estimate band and cup size
. Useful before shopping
. Simple measurement-based result
. Helpful for comparing different sizes
Common Uses of Bra Size Calculator
. Online lingerie shopping
. Finding a fitting bra
. Checking size after weight change
. Measuring before buying sports bras
. Finding a daily wear bra
. Comparing new sizes
. Understanding cup. Band size
When Should You Recheck Bra Size?
Your bra size may change over time due to factors. It is an idea to recheck your size if:
. You gained or lost weight
. Your current bra feels uncomfortable
. The band rides up at the back
. The cups feel too loose or too tight
. Straps dig into your shoulders
. You are buying bras from a brand
. Your body measurements have changed
Tips for Better Bra Fit
. The band should sit flat. Firm around your body.
. The cups should fully cover without gaps or overflow.
. Straps should support gently without digging into the skin.
. The center part of the bra should sit close to the chest.
. The bra should feel comfortable when moving, sitting and standing.
. Different brands may fit differently so always check size charts.
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Asked Questions
> What is a Bra Size Calculator?
A Bra Size Calculator is a tool that estimates your bra size using your band and bust measurements.
> How is bra size calculated?
Bra size is usually calculated by comparing the measurement with the bust measurement. The underbust measurement helps estimate the band size and the difference between bust and band helps estimate the cup size.
> Is the Bra Size Calculator accurate?
The calculator gives an estimated size based on sizing methods. Final fit may vary depending on brand, bra style, fabric and body shape.
> Can I use this calculator for shopping?
Yes. It can help you choose a starting size before buying bras online. You should also check the brand’s size chart before purchasing.
> What measurements do I need?
You usually need two measurements: measurement and bust measurement.
> Should I measure in inches or centimeters?
You can use the measurement unit supported by the calculator. If both options are available choose the unit you’re most comfortable with.
> Why does my bra size change?
Bra size can change due to weight changes, age, pregnancy, breastfeeding, exercise habits, hormonal changes or body shape changes.
> What if my result is between two sizes?
If your result falls between two sizes you may try both sizes. Choose based on comfort. Some people may need a sister size for a fit.
> What is a sister size?
A sister size is a bra size with a similar cup volume but a different band size. For example 34B and 32C may have cup volume but different band fitting.
> Can the same bra size fit differently in brands?
Yes. Bra sizing can vary between brands and styles. A size that fits well in one brand may feel slightly different in another.
Finding the bra size is important for comfort, support and confidence. The UseToolsPro Bra Size Calculator gives you an simple way to estimate your bra size using basic measurements.
Whether you are buying a bra online checking your current size or looking for a more comfortable fit this calculator can help you make a better choice. Enter your measurements calculate your size and use the result as a starting point, for finding the right bra.