Free · Instant · Two measurements
Find your correct bra size in under a minute
Most women in India are wearing the wrong band or cup. Grab a soft measuring tape, enter two numbers below, and get your band size, cup size, and the equivalent across US, UK, EU and France sizing.
Tape snug and level, directly under the bust, over a well-fitted non-padded bra.
Tape loose and level across the fullest part, without compressing the tissue.
Please enter both measurements to continue.
Copied to clipboard
A rough shape guide — actual cut varies by brand and style.
International conversion
See your size across sizing systems
There's no passport-free version of bra sizing — the same body can be a 34B on an Indian shelf, a 34B in a UK store, a 34B in the US, and a 75B once you cross into France. Cup letters only start pulling apart from D upward. Calculate above and your row lights up below.
| India / UK | US | EU / France | Band (cm) |
|---|
The method
How we calculate your size
Most tailors and fitters have quietly moved away from the old "add four or five inches to your underbust" trick — it dates back to a time when elastic simply didn't stretch the way it does now. We use the more modern direct-measurement approach instead.
Wrap the band
Run the tape firmly around your ribcage, right under the bust, keeping it level front to back. Round that number to the nearest whole figure — that's your band, no adjustment needed.
Wrap the bust
Now measure loosely across the fullest part of your bust. The tape should lie flat, not squeeze — you're capturing shape, not compressing it.
Read the gap
Take the bust number and subtract the band number. Each inch of gap steps you up one cup letter: a 1-inch gap is an A, 2 inches a B, 3 a C, and onward.
cup difference = round(bust, in) − band
0=AA · 1=A · 2=B · 3=C · 4=D · 5=DD/E · 6=F · 7=FF · 8=G
Worked example
Say your underbust comes in at 78 cm (≈30.7″) — that rounds up to an even band of 32. Your bust measures 96 cm (≈37.8″), rounding to 38. The gap between them is 6 inches, which lands on an F cup, giving 32F. If that particular size is hard to find on the shelf, try 34E or 30FF as a sister size instead.
Before you shop
Common measuring mistakes
Measuring over a padded bra
Foam or moulded cups quietly inflate the numbers. Strip down to a thin, unpadded bra — or nothing at all — before you pick up the tape.
Cinching the band too hard
Snug is right, strangled isn't. You should still be able to tuck two fingers comfortably under the tape at the back.
Letting the tape tilt
A quick mirror check helps — the tape should sit level all the way round, not creep upward at your sides or back.
Treating one label as gospel
Every manufacturer cuts to its own block. Use your calculated number as a launchpad, then let actual fit have the final word.
Skipping the sister size
Out of stock in your exact number? The neighbouring sister size almost always carries the same cup volume.
Assuming it never changes
A shift in weight, a new training routine, pregnancy or nursing — any of these can quietly move both numbers within a season.
Questions
Frequently asked questions
Showing our top 15. See the full FAQ page for all 20, with search.
Close enough to shop with confidence, but not a guarantee — fabric stretch, wire shape and each brand's own cutting pattern all nudge the final fit one way or another. Think of the number as your opening bid, not the final word.
Because no two manufacturers cut from the same block. A 34B at one counter can sit like a 34C at another — perfectly normal, and exactly the gap that sister sizing is built to bridge.
Skip it — that trick belongs to an older era of stiffer fabric. Today's fitters, and this calculator, work straight off your actual underbust number with no padding added.
Think of it as a size that holds the same cup volume one band over. Shift the band up a notch and the cup down a letter (or vice versa) and you land on a size that fits almost identically — useful when yours isn't in stock.
Once or twice a year is a sensible rhythm, and always after anything that changes your shape noticeably — a shift in weight, pregnancy, nursing, or surgery.
It can feel that way at first, but a loose band creeps up your back and hands all the support job to your straps — the opposite of comfortable by evening. A band that sits level and snug on the loosest hook does the real work.
Elastic simply gives with time and washing — that's not a sizing mistake, it's why every band ships with two or three hook rows. Move in a hook rather than buying a size down.
The number stays the same, but wire-free and soft-cup styles often run a touch roomier in the cup, so plenty of people drop a cup size when switching to wire-free.
Absolutely — band and cup only describe circumference and volume, not shape. Root width, projection and overall breast shape still vary widely between two people wearing the identical label.
Cup volume is usually the first to move with weight change, pregnancy or nursing, while the underbust band tends to hold steadier over time.
Very common, and nothing to worry about. Fit the cup for your larger side, then tuck a thin insert into the smaller cup if there's a gap.
Band level and staying put on the loosest hook, centre gore lying flat against your breastbone, and cups holding everything with no spilling over the top or gapping at the sides.
Above a D cup, there was never one agreed global standard, so each brand went its own way with labelling — some use DD, others jump to DDD or E for the same volume. Check that specific brand's own chart when in doubt.
Reach for the sister sizes shown alongside your result — same cup volume, different band, and usually much easier to actually find in stock.