How can you tell what bra size you need to wear?

[Rainbow Dash]

I'm pretty sure the ones I have are too small for me. I have no idea how to tell :/

[Melody Pond]

I can usually tell when I need to go get remeasured and get new bras.
I wear wired bras and when I start to get a red mark where they are digging in even on the loosest fastening I know they are too small around my bust.
Also read marks on my shoulders when on the loosest is a good hint.
Also sometimes the back part starts to ride up when wearing it.

Sometimes they feel too small and I kind of adjust it, the straps and the fastening at the back and loosen everything and it is fine then.

If your boobs are kind of spilling over the cups then the cups size is too small.

If you think they are too small then you can always go to a local shop and get measured just to check. Marks & Spencers and La Senza do it for free.
You can measure it yourself for a rough guide too but it is best to see a professional.

This is really useful and tells you how to measure your bra size yourself.
http://www.bbc.co.uk/dna/h2g2/A4455272

EDIT: I have just found this site too
http://womens-intimate-apparel.suite..._your_bra_fits
It basically says if any of these happen your bra is too small

Breasts are touching – giving you that uniboob look.
Breasts spill over the top or the sides of a bra.
The back of the bra is riding up and is not level with the underwiring at the front.
There is no gap between the breast and underwiring.
Indentations of bra straps on the shoulders.
The wearer is overly-conscious of a bra when wearing it.
The bra chafes the skin, causes skin abrasions, or digs into the breast itself.
There is wrinkling in the cup, due ot excess fabric — bra is too big
There is wrinkling in the cup at the very tip — bra is too small
The bra moves when arms are raised

[losing touch.]

Just go and get measured. M&S is a good bet, they're usually very knowledgeable and can advise you on what sort of bras to buy. You could measure yourself but personally i think it's better to get someone else who knows what they're doing to do it.

[Rainbow Dash]

Ah, awesome I'll go to M&S. Thanks for the list, I'm pretty sure they are too small now

[Magic.]

Personally I wouldn't recommend M&S ... they measured me as a 38 back, and my mum as a 30 back, even though she's four/five dress sizes bigger than me, and so I obviously have a smaller back than her ... :\ I'd recommend somewhere Debenhams, they usually have a specialist lingerrie department, which is good because they'll have loads of different ranges.

[MegaMadness]

Yeah, getting measured is the best way to know for sure. I'm so glad I did.

[The Morrigan]

http://www.mysecrethealth.com/how-to...e-bra-cups.htm

If you wanted to measure yourself at home then this website tells you what to do. I've always measured at home and my bras have been fine

I prefer measuring at home as if I had it done in a shop I'd feel pressured into buying a bra and the places that actually do measuring are a bit out of my price range

[rita123]

you can measure yourself.

[dropsofjupiter]

I agree with anyone who's said get measured at M&S, but remember that different shops sell completely different sizes, for example, in one shop I am a 32B in another I'm something ridiculous like a 36C and they both look the same size to me! So buy from whichever you got measured at =']

[.Brittany.]

Your best bet also, would to be to go to your local bra store, and they can measure you and tell you.

[Chiyokocho]

Personally I wouldn't trust any of these bra-measuring things in stores like M&S or Debenhams... I'd reccomend going to an actual lingerie store dedicated to just that and getting a proper measurement... You'll never believe the difference in size you might have. M&S measured me as a 34B, which I wore for years in ignorance. When I got my size checked for real in a Bravissimo, I found out I was a 30FF, so it's worth making the effort.

[Melody Pond]

Originally Posted by Chiyokocho

Personally I wouldn't trust any of these bra-measuring things in stores like M&S or Debenhams... I'd reccomend going to an actual lingerie store dedicated to just that and getting a proper measurement... You'll never believe the difference in size you might have. M&S measured me as a 34B, which I wore for years in ignorance. When I got my size checked for real in a Bravissimo, I found out I was a 30FF, so it's worth making the effort.

From what I have experienced that usually isn't the store that is the bra. Every brand of bra has a different size scale.

I have found that I have to get measured in each store individually and each one varies usually not by much but it does vary. The all fit me the same and I can't feel which one is smaller. When I hold them up together they are the same but the actual size is different.
I tend to stick to the same few shops so I don't have loads of different sizes to remember.

One thing I did find was when I went to a specialist shop they measured me way to big and then that bra was more expensive because it was bigger which made me feel like they just wanted more money out of me.

Oh also Debenhams is crap, I worked there and they put Christmas temps on bra measuring and they had never done it before. They just gave them a piece of paper with a size guide thing on it telling them how to work out the size. So now I don't trust any of them as I don't believe they are trained correctly.