Bra Fitting by Sight


Fit like the Professionals:

find the right size with our ‘fit by sight’ bra fitting guide


If you have a bit more time, and fancy becoming your own bra fitter, follow our guide to ‘bra fitting by sight’, just like the professionals , but in the comfort of your own home. It’s a great skill to try out on your friends and can lead to a fun girls’ night in without the need to go topless!


The most experienced and skilled professional bra fitters are able to look at a customer and instantly tell them the bra size they need. This can be a real wow for customers, and usually takes years of practise. However, by borrowing a few of the tried and tested techniques from the professionals, you can create your own fitting room at home and make sure you and your friends buy the perfect bra size. Here’s how….



Get Fitting!

Before you begin you’ll need:


  • A mirror that allows you to see the top half of your body from the front, side and back
  • To wear one of your newest, best fitting bras, fastened on the loosest hook with the straps adjusted about half way up – make sure you know the exact size of the bra you are wearing

It sounds silly, but many of us don’t have our bras on right in the first place! Put your bra on and fasten it in the normal way (it doesn’t matter how you do this), then bend forward and put your right hand into your left bra cup and pull the breast tissue fully into the cup from the side. Do the same with the left hand and right cup.


Now stand up and using both hands, wiggle the bra band around to make sure it sits just under your breasts.


Finally, pull the fabric of the cups up to remove any bulges. This is commonly known as the scoop and swoop ! (We like to refer to it as the jiggle and wriggle!)



80% of the support in a bra comes from the back band being firm, with the straps only needing to provide 20% of the support, so it's important that your back band is firm enough. The straps are designed mainly to allow you to adjust the cup of the bra and should not be relied on for your support (in fact you should be able to pull the straps of your bra down and find your bra doesn’t really move when it is ‘strapless’). Here are two different methods to use to calculate your back size – use them both and you should find that they bring you to the same or a similar conclusion.

Stand side on in the mirror. Your bra band should form a straight horizontal line across your body when you look at it side on. You should be able to put two fingers underneath the band but not pull it out any more than that.


Signs that it is wrong:

  • If the band is higher at the back than at the front then the back size is too big. Go down a back size. E.g. from 36 to 34. 
  • If you can fit more than two fingers under the band at the back, then the back size is too big. Go down a back size. 
  • If the back band is moving towards your shoulder blades on the tightest setting, the back is probably two sizes too big. Go down two back sizes. E.g. from 36 to 32.
  • If you can’t fit any fingers under the band and it feels uncomfortably tight, then the back size is too small. Go up a back size. E.g. from 36 to 38

Now look at the straps of your bra. Straps should sit firmly in the middle of the shoulders without digging in or leaving indentations, and require tightening half way.


Signs that it is wrong:

  • If the bra straps are leaving indentations in your shoulders or falling off, then the back size is too big. Go down a back size.
  • If you lower your bra straps and the bra starts to move around, then the back size is too big. Go down a back size.
  • If the bra straps are digging in and your breasts are sitting low at the front, the back size of the bra is too big. If your breasts are supported but the straps are digging in then this suggests the straps are too tight. Loosen the straps and if they are still too tight, go down a back size.
  • If the straps do any of these when they are fully tightened, then the back size of the bra is probably two sizes too big. Go down two back sizes. 




Use step one first to find your new base cup size (if your back size has changed, then your starting cup size will have changed too!) Then there are three different methods to use to calculate your final cup size – use them all and you should find that they bring you to the same or a similar conclusion .

If your back size has changed you will automatically need a different cup size before you even start! For example, if you found that you needed to reduce the back size by one or two sizes, you will now need to automatically increase the cup size by the same number of sizes to allow the same amount of room in the bra for your breasts.


We won’t bore you with the technical reasons, but rest assured that if you don’t do this before following the steps below, your bra will be too small.  So, if you started off wearing a 36B and discovered you should be in a 32 back, your starting size is a 32D i.e. a D cup size.

Facing the mirror look at the front of your bra, at the centre of your bra that sits between the cups. The centre of the bra should lie flat against your body, with no gaps.


Signs that it is wrong:

  • If the centre of the bra sticks out or there is any room between the centre piece and your body, the bra cup is too small. Go up a cup size. E.g. from your new base size of D to DD (if the designer doesn't offer DD, got to E)
  • If the centre hardly touches your body at all then the cup size of the bra is probably two sizes too small. Go up two cup sizes. E.g. from your new base size of D to E (or if the designer doesn't offer DD, go to F)

Now look at the cups of your bra. Your breasts should be fully contained in the cups with no gaps and nothing popping out (i.e. no ‘double boob’ effect!). When you try a top on and stand side on to the mirror you should see a smooth line under your clothes, with no bumps over the top of the cup.


Signs that it is wrong:

  • If your breasts spill out over the top or at the side of the cups rather than leaving a smooth line, the cups are too small.. Go up a cup size from your new base size.
  • If the over spill is very pronounced ( a double boob effect), the cups are probably two sizes too small. Go up two cup sizes from your new base size.
  • If there are gaps in the cup, even when you hold the back band as tight as possible, your cup size is too big (this is less common however and usually caused by the back band being too big so make sure you check this after holding the back band tight). Go down a cup size from your new base size.

Now turn in the mirror to see the wires of your bra. The breasts should be fully contained within the wire, the wire should clear the entire breast at the side and feel hard to touch with no ‘squidginess’!


Signs that it is wrong:

  • If the underwire at the side of your bra is soft and squidgy to touch, rather than firm, the cup size is too small. Go up a cup size from your new base size. 
  • If the underwire is sitting away from the body and touching the breast tissue, the cup size is too small. Go up a cup size from your new base size. 
  • If the wire is hardly touching the body and uncomfortably pressing against the breast tissue, the cups are probably 2 sizes too small. Go up two cup sizes from your new base size.
  • If the wire is uncomfortably far back under the armpit and there is a one inch or more gap between the wire and the start of the breast tissue, the cup may be too big, or it may simply be that you need a bra with a shallower cup. Go down a cup size from your new base size, or choose a bra with a lowe cut top in our Bra Style Guide.


Click to watch our Professional Bra Fitting video if you'd like to see how it's done!



After you have taken these final 4 steps you should be able to calculate your cup size – add the back size and cup size together, and hey presto: you’re a bra fitter!  All you need to do now, is sit back and go bra shopping!


Now you’ve mastered the art of fitting, the last thing to remember is that like shoes and clothes, different brands or styles of bra can require slightly different sizes. Once you know your standard size, you can also calculate your ‘sister sizes’ – i.e. the sizes that you’ll find may also work for you if your normal size isn’t available in a particular range, if you have a particular preference for a firmer or looser fit or if a particular make of bra is more tight or loose fitting that the standard (don’t worry by the way – when you browse our bras, our fitting notes will always tell you if that is the case!)


Simply find your standard size on our size chart, and you’ll see your sister sizes automatically calculated  - so whatever bra you like, you should be able to find a size that works! If you're shopping from outside of the UK, check our international size converstion charts.



Read what our customers have to say...

"I’m used to a professional fitting and find tape measures awkward so I thought I’d try the ‘fit by sight’ technique as I’ve had this done by a professional before and know it works. I didn’t expect to be able to do it as i'm not trained or anything but the video was great, it made it really simple to follow and to know what you were looking for and the ‘right and wrong’ pictures explained it all really clearly. The size charts were also useful – I loved a range that didn’t come in my exact size but with the pop up chart, I quickly found an alternative size that worked really well. Thankyou for helping me get the right size in a bra I normally would have thought I couldn’t have!" Diane D, Worcester, UK


"I can’t believe I’ve been wearing the wrong size for years  but after following your fit like a professional guide, I changed from a 34D to a 30F! To find that I’m slimmer than I thought with bigger boobs was a nice surprise – I’ve never felt sexier and my girlfriend thinks so too" Jessica S, Brighton, UK


"Your professional fitting guide was very informative. I always assumed that even if my back size changed, I’d still be the same cup size. Now I know that a b cup on a 34 back is different to a b cup on a 38 back and why my bras never used to fit" Liz S, Staffordshire, UK


"I thought the gaps in the cup of my bra meant my cup size was too big and am amazed to discover it was because the back size was too big. It just goes to show that it’s really worth using the professional advice available. Thankyou"  Claire R, London, UK


Click here to see some real life customer before and after pictures. No surgery has been performed, we promise!



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