If you’ve wondered what the average bra size in the US is, you definitely aren’t alone, my friend—I have too. But just a reminder: it doesn’t matter if you wear an XS triangle bralette , a 3XL racerback bralette , or you sometimes enjoy going braless , discovering that you may not be “average” shouldn’t be cause for alarm, disappointment, or insecurity! You certainly don’t need to be average to be beautiful, healthy, or happy. I’m not average and there’s a good chance you aren’t either. And that’s a-ok, pal!

Plus, after doing a bit of digging, I’ll tell ya that the answer to that question is not even the most interesting part about women’s bra sizes. There’s a lot to know about the average breast size for women that’ll take ya by surprise… So without further ado, let’s get to all your burning questions about breasts and bra sizes!

According to a survey of 40,000 women conducted in 2013 by lingerie retailer Intimacy, the average bra size in the US at that time was 34DD.

This means the average rib cage measurement is 34 inches and the average cup size is DD. Surprised? (Umm… I was!) However, other sources report that the average cup size in the US is a C . So the answer may not be that simple to determine. (Intimacy has since gone out of business and didn’t conduct any more surveys.)

There are reasons that this number may not be easy to identify (and I’ll get into that in a minute), but one thing we do know is that this number is not static. Since surveys like this were first conducted, the answer to this question has changed. A lot. And the average breast size for women in other countries is not the same either.

This question is very hard to answer, because there’s a wide range of averages in individual countries. In general, the average bra size in the US and in European countries are reported to be the largest. Average breast size for women is much smaller in African, Central American, and Asian countries.

One source claims that the average bra size worldwide is between a large A and small B cup, according to American sizing. In individual countries that average ranges from AA in many southeast Asian and central African countries to C or D in the US, UK, and Scandinavian countries. This makes it clear that being “average” really depends a lot on where you are! (And since it is largely determined by location, it isn't something you should drive yourself crazy shooting for or feeling bad about.)

The other reason this question is difficult to answer is that there have been no worldwide surveys where women have been measured or asked their size using the exact same scale of measurement. Like did you know there are at least SIX different bra sizing systems around the world?! Another thing the human population can’t seem to agree on, I suppose.

The answer to this question is a definitive “no.” In 1983 the average bra size in the US was reported to be 34B . This suggests a very large change in average breast size for women in the US in only twenty years!

Very likely, though women have not always worn bras, the average bust size has also changed in response to nutrition, activity level, and the genetics of the population throughout history. (As has the notion of any “ideal” size, which, remember my friends, is always a social construct!) Regardless of what the average is or ever has been, there are several factors that influence a woman’s resulting bra size.

There are two primary factors that influence a woman’s natural bra size. One is out of our control and one we have a degree of control over.

1. GENETICS

The biggest influence on the size of your natural breasts is likely genetics. This is obviously not something you can change or do anything about! But just like determining your hair or eye color, your genetics influence the size of your breasts when you reach adulthood.

2. WEIGHT AND ACTIVITY LEVEL

In studying the average breast size for women in different countries, there is a high correlation between BMI (body mass index) and average cup size. While BMI is an imperfect way of determining if someone is overweight or obese (especially if you lift weights and have built up your muscles!), women with a higher BMI do tend to have a larger average cup size.

Breasts are primarily composed of fatty tissue, so it makes sense that women who are heavier are more likely to have larger breasts. And women who are thin or underweight are more likely to have smaller breasts. Women in developing countries that are more physically active than women in the US are also more likely to have smaller breasts due to lower overall body fat percentage.

Interesting tidbit: while lifting weights and doing chest exercises can help lift your breasts and sometimes give the illusion of a larger bust, they can’t actually increase your breast size. Probably because exercise doesn’t increase fatty tissue and there are no muscles in breasts you can increase through exercise. The more you know!

These reported changes in bra size are much larger than what I experienced when my friends and I repeatedly chanted “we must, we must, we must increase our bust” in middle school. While there are some very real reasons for this increase, none of them is a chant learned in a Judy Blume book! Here are a few real possibilities:

1. INCREASE IN AVERAGE BMI

In the last several decades, the average weight of American women has increased substantially . As the percentage of women who are overweight and obese has increased, it makes sense that average bra size has increased also.

2. INCREASE IN NUMBER OF BRA SIZES AVAILABLE

The number and range of bra sizes available today are much greater than they were in past decades. This could mean that women who used to squeeze into smaller bras are now wearing the proper size. There has been a growing emphasis on the importance of size inclusive clothing, which is a very good thing! (And this is why both WAMA hemp bra styles come in sizes XS-3XL designed to fit traditional bras sizes ranging from AA cup to E cup!)

 3. BREAST AUGMENTATION

 Yep, I mean “boob jobs.” As these kinds of procedures have grown more popular they have given some women larger breast sizes than they would have had naturally. And this has likely raised the average breast size in the US!

According to statistics published by the American Society for Plastic Surgeons in 2018, over 313,000 women had breast augmentation surgery that year. In 2017 it was just over 300,000.

Even when you take into account the approximately 70,000 surgeries each year for implant removal and breast reductions, that still results in a net of 460,000 boobs ending each year significantly larger than they began! And these bigger boobs all need bigger bras!

Your bra size will likely fluctuate and change over the course of each month – and over your lifetime. This is completely normal! And there are a few reasons why:

• Your menstrual cycle: Fluctuating hormone levels can temporarily increase your breast size during that one week of the month. Underwires in conventional bras may feel more uncomfortable when your breasts are tender at this time. Ouch! (This is why bralettes are my BFFs this time of the month.)
• Sex: Likewise, hormones released during sex can also (very) temporarily increase your breast size. But there’s no need for a bigger bra for this short duration. (Maybe just don’t go bra shopping mid-orgasm.)
• Pregnancy/breastfeeding:  During pregnancy, breast size almost always increases due to weight gain and hormones. Post-delivery, as your milk supply comes in, their size increases even more. Then when you stop breastfeeding (or opt no to) they will reduce in size.
• Menopause: After menopause, your body’s estrogen production drops, and your bra size is likely to naturally decrease, too. You may find this a welcome change, or a complete bummer. Regardless, this is due to a loss of elasticity in your breasts' connective tissue and can’t be avoided. When it happens, reward yourself with some new proper fitting bras and bralettes (that’s what I plan to do)! And whatever you do, don’t feel bad about it. It’s natural!
• Birth control: Though not natural, hormonal birth control can also increase bust size .

Your bra size will likely fluctuate and change over the course of each month – and over your lifetime. This is completely normal! And there are a few reasons why:

• Your menstrual cycle: Fluctuating hormone levels can temporarily increase your breast size during that one week of the month. Underwires in conventional bras may feel more uncomfortable when your breasts are tender at this time. Ouch! (This is why bralettes are my BFFs this time of the month.)
• Sex: Likewise, hormones released during sex can also (very) temporarily increase your breast size. But there’s no need for a bigger bra for this short duration. (Maybe just don’t go bra shopping mid-orgasm.)
• Pregnancy/breastfeeding:  During pregnancy, breast size almost always increases due to weight gain and hormones. Post-delivery, as your milk supply comes in, their size increases even more. Then when you stop breastfeeding (or opt no to) they will reduce in size.
• Menopause: After menopause, your body’s estrogen production drops, and your bra size is likely to naturally decrease, too. You may find this a welcome change, or a complete bummer. Regardless, this is due to a loss of elasticity in your breasts' connective tissue and can’t be avoided. When it happens, reward yourself with some new proper fitting bras and bralettes (that’s what I plan to do)! And whatever you do, don’t feel bad about it. It’s natural!
• Birth control: Though not natural, hormonal birth control can also increase bust size .

Your first thought may be to wonder if larger breasts lead to a greater risk of breast cancer . Studies indicate that the answer is no, but there are two types of medical conditions related to bra size in women: physical and mental.

One study in the UK revealed that larger breasted women are slightly more likely to be dissatisfied with their wellbeing, health, and body image. In particular, larger breasted women are more likely to report upper back pain and have posture problems. Pain during exercise and difficulty getting comfortable to sleep are also more common for those with bigger busts.

A rare condition called breast hypertrophy occurs when a woman's breasts comprise over 3% of her body weight. This condition can result in all the problems noted above. However, the most common condition large breasted women are likely to experience is a mental one: women with large breasts are more likely to experience depression, low self-esteem, and anxiety . Similar feelings are also common in women with breasts of significantly different sizes .

Ladies, let’s not be so hard on ourselves! All breasts sizes and shapes deserve appreciation and respect!

It’s commonly said that most women are wearing the wrong bra size. This belief was verified by a small study conducted in 1998 and another one in 2008 that showed that 70% of women are wearing bras that are too small and 10% are wearing bras that are too big.

So it might very well be true that 4 in 5 women are wearing the wrong size bra. But of course, you want to be in the 20% of women who are wearing the right size! And the best way to avoid wearing the wrong size bra is to learn how to measure yourself properly to determine the correct size. (During all those alternately embarrassing and boring hours of high school health class why didn’t they spend a few minutes teaching us this? It’s actually very useful!)

A 2011 study done in the UK found that most women do not know how to properly measure and evaluate if they are wearing the correct bra size. Even if a woman knows her bra size in one brand or manufacturer, because there aren’t industry-wide standards for sizing, this can still lead her to choose a bra that does not fit properly. (That explains a lot for me!)

WAMA’s underwear size chart can help you find the right size bralette for you. And one of the nice things about bralettes is that due to their stretchiness and lack of structure, they’re much more adaptable to a range of sizes. No matter if you have raging PMS or if the needle on the scale is going up or down, they are like that true friend who supports you no matter what. (And reminds you that you always look fab.)

Sadly, one study revealed that worldwide a whopping 71% of women are dissatisfied with their own breast size ! But hopefully, now you know that healthy breasts come in all shapes and sizes, the result of factors both within and beyond our control. Whether your bra size is smaller, larger, or average, that doesn’t mean it’s any more “right” or “wrong”. Please don’t compare and despair!

There’s no ideal bra size, there’s only personal preference. And no matter where you are in life and on the breast size continuum, I hope you give your ta-tas the love they deserve. And that includes a well-fitting bra or bralette! If it’s been a while since you’ve checked your current bra size or wondered, “ how many bras should I own ?”, think about it. They deserve your love and support (pun intended)!

Which of these facts related to the average bra size in the US and average breast size for women around the world surprised you the most? What tips do you have for other women to learn how to love and accept their breasts just the way they are? Drop ‘em like they’re hot in the comments!