Believe me. Measuring your own bra size gives you more control when looking for a bra. Discover your best bra size (or sizes) easily from your own home.
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Why should I know my own sizes?

Maybe you’re buying a bra for the first time. Or you’ve been wearing the same size for a long time.
Researches tell us that many women wear the wrong sized bra. So it’s no luxury to get into the matter of bra sizing a bit yourself.
Remember that sizes can be very close.
Check your size in my bra calculator
of visit M&S for advise and size chart

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A slight change in your measurement could mean a whole new bra size.
It could be that you need 80B instead of 85C. Or 70C instead of 70A.
Exactly how to measure yourself?
Ask someone to give you a hand if you like.


- stand for a mirror
- measure on bare skin or wear a bra without padding
- ask someone to help if you like it
- write down the measurements
Your underbust and bust size measurements determine your bra size.
That’s all you need.
Well, there is of course a calculator or bra size chart you’ll need to find out.
Will my bra size change over time?

Some of us might wear the same bra size as they did 20 years ago. Others might need many different sizes in their lives.
There are different causes that may change our bra size during life.
Are you in between two possible bra sizes? If this is the case, it might be difficult to choose your best bra size. I do advise trying also your possible sister sizes. Remember that different brands may have a different fit, so it’s best to just try them both.
Other articles you might like
Measuring guide on all topics
Why it’s best to handwash your bras
How to choose a comfortable bra band size?
About the average bra size UK
How to use UK bra size chart
Why is my bra hurting me?