FAQ
Bra Size and Fit Questions
Direct answers about calculator results, measuring, sister sizes, international conversion, fit problems, breast shape and privacy.
Calculator Results
Why is my calculated cup bigger than expected?
A cup letter is relative to the band it's paired with, not a fixed volume. A smaller band paired with a bigger-looking cup letter can carry the same or less volume than a larger band with a smaller-looking letter. A bigger cup letter than you're used to isn't automatically wrong.
Is the result exact?
No - it's a measurement-based starting point. Brand, style, fabric and your own shape all affect how a labelled size actually fits, which two or six measurements alone can't capture. Treat the result as the first size to try, then confirm it with a fit check.
What if I am between two band sizes?
When your underbust measurement sits close to the midpoint between two band sizes, the calculator shows both as a starting comparison instead of picking one silently. Try the closer one first, and use the sister size of the other if it doesn't work out.
Measuring
Should I measure with a bra on?
Measure the underbust without a bra, or in an unpadded one, so the tape reads your actual ribcage. Measure the bust without a padded or moulded bra too, since padding adds volume the calculator would otherwise count as yours.
Band and Cup Sizes
Why does a D cup look different on different bands?
Because a cup letter describes a volume relative to the band, not an absolute size. A 30D and a 38D carry very different amounts of tissue despite sharing a letter - the band number is what makes the letter meaningful.
Sister Sizes
Are sister sizes identical?
No - they share an approximate cup volume, not an identical fit. Band tension, strap position and wire geometry all change with the band size, so a sister size is worth trying, not assuming will fit exactly the same.
International Conversion
Why do brands use different labels?
Past a D cup, the US market in particular has no single agreed cup-letter sequence - different brands use DD, DDD, E or F for the same relative volume. Our converter shows a common label and flags the accepted alternative rather than picking one as definitively correct.
Fit Problems
Can gaping mean the cup is too small?
Usually not directly - gaping more often points to excess volume or a shape mismatch than to a cup being too small. It can still be worth testing a smaller cup, but the band-only test and cup shape are better first signals than assuming it's a straightforward size issue.
Breast Shape
Can breast shape change the size I need?
Shape doesn't change your measurement-based starting size, but it does change which cup construction actually contains that volume comfortably. Two people with the same size can need very different cup shapes.
Privacy and Saved Measurements
Are my measurements stored?
Not unless you explicitly choose to save them on this device. Measurements stay in your browser during a calculation and are never sent to our servers or included in analytics.
How can I delete saved measurements?
If you've saved a result on this device, a delete option is available wherever it's shown. Clearing your browser's local storage for this site also removes anything saved here.