Find My Size

Plus-Size Bra Size Calculator

Finding the right bra size should not feel complicated. True Bra Size helps you calculate a practical starting size using just two simple body measurements.

6+

Units

3

Rounding modes

6+

Units

1 MEASURE
2 FIT QUIZ
3 RESULTS

Step 1 — Your Measurements

Measure on bare skin or a thin unpadded bra.
Under ribs, firm but not painful. Exhale and measure.
Level, parallel to floor. Do not compress tissue.
Optional: Leaning bust measurement Lean forward 90° and let tissue hang naturally, then measure. Improves cup accuracy for projected and pendulous shapes.
Please enter both your snug underbust and standing bust measurements.
YOUR ESTIMATED BRA SIZE
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Bra Size Calculator
Breast Volume
Ptosis Grade
Ptosis Grade
Expansion Ratio
Breast Weight
Shape Identifier
Length Converter

Your privacy, gently protected 💕 Every measurement is calculated right here in your browser — we never store, never save, and never share it. Close this page and everything quietly disappears. Your body, your data, your choice. Want to keep your result? Screenshot or copy it before you go.

Find your starting bra size

Use a soft tape and enter two measurements. We will show the result in the sizing system you shop in. Use a soft tape and enter two measurements. Use a soft tape and enter two measurements. 

  • 1 cm = 10 mm = 0.3937 in

  • 1 inch = 2.54 cm = 25.4 mm

  • 1 foot = 12 in = 30.48 cm = 0.3048 m

  • 1 meter = 100 cm = 39.37 in = 3.281 ft

  • 1 yard = 3 ft = 36 in = 0.9144 m a1 cm = 10 mm = 0.3937 in

  • 1 inch = 2.54 cm = 25.4 mm

  • 1 foot = 12 in = 30.48 cm = 0.3048 m

  • 1 meter = 100 cm = 39.37 in = 3.281 ft

  • 1 yard = 3 ft = 36 in = 0.9144 md

How to Measure Your Breast Size

Your privacy, gently protected 💕 Every measurement is calculated right here in your browser — we never store, never save, and never share it. Close this page and everything quietly disappears. Your body, your data, your choice. Want to keep your result? Screenshot or copy it before you go.

Step 1 — Measure your underbust: Stand upright wearing a non-padded bra. Wrap the measuring tape around your ribcage, just under your bust. Make sure it’s snug but not too tight — that’s your band size (underbust measurement). Write down the number.
Step 2 — Measure your bust: Measure around the fullest part of your bust, keeping the tape parallel to the floor. Don’t pull it too tight — this is your bust measurement. The difference between your bust and underbust measurements determines your cup size.
Step 3 — Use our breast calculator: Enter your measurements into the breast calculator above to get your bra size across US, UK, EU, FR, and AU sizing systems instantly. For the most accurate results, measure first thing in the morning and avoid measuring during your menstrual period when breast tissue may be swollen.

Bra size calculator FAQs

How do I calculate my bra size?

Measure your snug underbust and loose full bust, then enter both numbers into the calculator. The underbust helps determine the band, while the difference between the full bust and band helps determine the cup.

Measure your snug underbust and loose full bust, then enter both numbers into the calculator. The underbust helps determine the band, while the difference between the full bust and band helps determine the cup.

Measure your snug underbust and loose full bust, then enter both numbers into the calculator. The underbust helps determine the band, while the difference between the full bust and band helps determine the cup.

Measure your snug underbust and loose full bust, then enter both numbers into the calculator. The underbust helps determine the band, while the difference between the full bust and band helps determine the cup.