How Big Should A 12 Year Old Girl's Breast Be?

It all depends on your genetics, weight,  and even sports you do. I'm twelve and a half and I'm a 36D, but I also got my period in third grade. Most of my friends (although we are in seventh grade) havent even gotten their periods yet and they are as flat as boards. Its not that great having big breasts and I wouldnt wish if upon anyone. Certain cloths don't look good, boys call me rude names, and many sports arent easy. To all the girls that arent happy with their small bra size, eventually youll have big boobs and until that time comes, don't stress about it. Learn to love your body- its what makes you you!
Hope I helped! =)
-francesca

I am 12 and I have a 30a sized bra, I wish I was a tiny bit bigger but girls should like their boobs the way they are so don't worry about what size you are because no matter what your bra size is will not matter when it comes down to important things xxx

Well I'm a 32A or 32B. Haven't checked really. My mom bought me 32A bras and now they're a bit tight, plus when I got measured I found out I was a B but I haven't had time to go bra shopping because I do some sports and run. Plus I have other stuff etc. My moms a 36D and she kinda teases me about being small but whatever. I got used to it. And anyways, I just use a cami because my shirts r too tight most of the time for bras bc ive grown some. Some of my friends need bras but I think are embarrassed about it. Also, one of my friends is huge, comparing to the other girls in our grade. So average is anywhere, you could be a late bloomer and have from 28AAs - 38DDs, just matters on heredity and how fast your body grows, plus when it starts/ed. I started in the summer before 5th, and I'm going into 7th. Birthday was in early March. I'm 5'2 1/2-3" and 90 lbs.

I turned 12 in January 2010, and I was a 32A. Now, I'm a 34B except for my strapless bra is a 32B because I need the tight fit. The average size is 32A-36B but some girls are bigger or smaller. Be happy with what you have!

Well, I'm 5'2 and a half, weigh 120 pounds, and have nothing at all, where as other girls in my grade are 11, weigh 90 pounds, and are wearing b cups..... It doesn't really matter, and we shouldn't be forced to grow up fast and be pressured about stuff like this.

I turned 12 June 2010 and I got measured this weekend. I am a 32a/aa depending on the style. There is no average size really, you just need to get measured to find your size, also there people will have bigger boobs or smaller boobs than you depending on there size or shape.
Everyone's boobs are a size to fit them and there body so don't worry   about if you are smaller or bigger than everyone els in your class. As above, I am 32a/aa but one friend is my height and size with boobs size 34b/c. I am not worried that mine are smaller than hers because my other friend has nothing!!!
Seriously, don't worry
hope this helps

Well when I was 12 I was a 34A now I'm 13 since december 7th and I'm a 36C everyone says it looks too big for me because I'm skinny but I don't belive that I think I'm perfectly fine because all you have to do is love your self how you really are not for what everyone is.

I get my breast growth from my dad's side. When I was in 4th grade I started growing. When I was 11 I was like a 34a. Then back in December I was a 34b. Now I'm a 32d/32dd. It's funny how much we grow.

I'm 12 and I weigh about 56kg and I'm 5'6. My size is 32B but I can fit into a C. My mom said the next time she buys me a bra , its going to be a C. Because when she bought the 32B, it was the right size, a little hanging out the sides but it was all good. Can't believe I'm almost a C, it was last year I struggled to fit into an A.

It all depends. I was about a 32A when I was 12 and now I'm 14 and I'm a 36B. So like people can develop very fast

Well, I'm almost 14 now, I'm a 36D and all my friends are still in A/B but I'm the oldest in my class and everyones smaller than me., I find it wierd being the biggest but its genetics mostly. I'm 36D and my moms only a 36B . I was a 34C when I was 12 if that helps and all my friends were FLAT!

I am a 34A but my friend (only 4 days younger) hasn't even started
wearing bras yet. She is tall; I'm short and we both weigh the about
same. I started growing in 4th grade and I'm going into 7th. My friend
started growing in 6th grade (also going into 7th). We started growing
at different times. When we are both done growing though, she could be a
lot bigger than me. Everyone starts and stops growing at different
times. No one has a perfect size chest. Don't stress. You'll catch up
with your friends or your friends will catch up to you.

Hope I Helped

~Megan

I'm nearly 13 and flat as a board.  I have tried tried training bras but they won't stay on me properly.  My mother likes me to wear something and insists I wear vests which is embarassing at my age.

l'm a 32 B. L'm 12. L guess lt's pretty small compared to others but breasts size shouldn't matter really. But there is no real average.

I'm 12 almost 13 and I still wear training bras size small so it's kinda embarrassing

This should be the age when the breasts are first starting to develop so there is no need to worry about the size at this age.

I am only 9 and I wear a padded bra every wear I wear a size 32A once I went to school I had been sick so my friend gave me a get well hug and said can I look and your boobs they feel huge I said ok but it was only because I had 2 bras on .

Well,I turned 12 in late march and now I am a size 32B
I think I weight 120 pounds and my height is 5'4
I would like to go up 1 more size before I turn 14!!!!