Find your starting bra size.
Measure, understand your UK size, and check what feels right when you try a bra on.
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- UK sizes
Your measurements stay on this page. We do not store them, put them in web addresses or send them anywhere.
Something feels wrong? Use the fit checker
Already know your size? Jump to a tool
Before you start
Measure in three steps
A soft tape measure, a mirror and two minutes. Your result is a starting size; the fit when you try a bra on matters more than the number.
- 1
Underbust
Wrap a soft tape snugly around your ribcage, right under your bust. Keep it level and breathe out.
- 2
Bust
Measure around the fullest part of your bust with the tape relaxed. Leaning forward slightly helps.
- 3
Try it on
Check the band, cups and straps in the mirror. Our fit guide tells you what to look for.
Bra styles
Same size, different fit
A plunge, a balconette and a full cup can carry the same label and still sit completely differently. Here is what each one changes.
- Full cup Spilling over lower-cut cups
- Balconette Gaping at the top of fuller cups
- Plunge V necklines
- Non-wired Wires that dig in or poke
Fit check
Something feel off?
Pick what you notice. Each card opens the part of the fit guide that explains it.
- Band rides up at the back Usually not firm enough to stay level. Check the hooks and band size.
- Cups gape at the top The cup may be too big, or the style may not suit your shape.
- Spilling over the cup Often a cup that is too small, or a neckline cut too low for you.
- Straps keep slipping Strap length, position and the band all play a part.
Our method
How it works, and what it cannot do
We use the tape method published by two UK retailers, Brastop and Boux Avenue. Your underbust is rounded up to an even band, and each inch between your bust and that band is one UK cup step. Nothing is added to the band.
How bra sizes work-
Starting point
Tape measurements cannot see breast shape, so the result is a size to try.
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Brands differ
UK brands and styles fit differently. Always check the brand’s own size guide.
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Honest range
UK bands 28 to 48 and cups AA to L. Outside that, we say so instead of guessing.
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Not medical advice
If a bra causes pain that does not ease, speak to a health professional.
Buying guides
Shop by what you need
Strapless for a big bust, sports bras that stop the bounce, nursing bras and more: what to look for and which size to pick.
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Occasion and outfit Strapless bras for a large bust Read the guide -
Fuller bust and plus size Sports bras for big busts Read the guide -
Occasion and outfit The right bra for a backless dress Read the guide -
Everyday support Minimiser bras: a smoother, closer shape Read the guide -
Comfort and life stages Nursing bras: when to buy and how to size Read the guide -
Occasion and outfit Push-up bras: choosing the right lift Read the guide
Everything else you might need
- How to measure Step-by-step, with diagrams.
- UK bra size chart Band and cup tables in inches and centimetres.
- Sister sizes A similar cup volume on a tighter or looser band.
- Size converter Read US, EU, French and Australian labels as UK sizes.
- Brand guides How Freya, Panache, Curvy Kate and others label sizes.
- Find bras Search UK retailers by your size.