When people talk about breast size, they often describe it in terms of bra size. The average bra size in the United States is 34DD. That said, average breast size does not necessarily equate “normal” size.

Average breast size can vary by country. In the U.K., for example, the average is 36DD. But pinning an exact figure for what’s “average” isn’t as easy as you might think.

We generally think of the average breast size as a measurement of natural busts. But as the average size increases over time, it’s possible that augmented breasts are being included, too.

Read on to learn more about how breasts are measured, which factors influence bust size, reasons for fluctuation, and more.

In order to use bra sizes to accurately measure the average breast size, everyone would have to be on the same page about which bra sizes go on which breasts.

But we don’t exactly have a universal understanding of the correct bra size.

In fact, an estimated 80 percent of people are wearing the wrong bra size. Most don’t realize it for a variety of reasons.

For example, it’s possible that your bra size was measured incorrectly.

Different stores may use different methods of measurement, and human error may also lead you astray. Bra sizes can also vary across brands.

Your breasts can also change in size over time.

So, if you’ve been wearing a 38C for quite some time or are switching brands, you may want to consider getting resized.

You’ll need three different measurements to determine your overall breast size, including:

  • length across your breasts (bust)
  • length around your torso (band)
  • overall breast volume (cup)

You can find your bust size by wrapping measuring tape around your body where your breasts are fullest — usually over your nipples — while wearing an unpadded bra.

Your band size is the length around your torso, which you can find by wrapping measuring tape around your body just below your bust.

You can find your cup size by calculating the difference between your bust size and your band size. Consult a sizing chart to determine which cup letter this figure corresponds to.

It’s one thing to know how the size of your breasts compares to the average. But are your breasts the “right” size?

That depends on how you feel. The most important thing to consider is whether you’re comfortable with the size of your breasts.

Some researchers from medical website Zava tried to find out what people consider to be an ideal breast size.

A survey of more than 2,000 people revealed that about 60 percent of men and 54 percent of women find average-sized breasts more attractive.

When pressed for specifics, about 53 percent of women and 49 percent of men shared they prefer a C cup.

That said, almost 70 percent of respondents said they’re happy with the size of their partner’s breasts.

At the end of the day, it doesn’t matter how other people feel. Your individual comfort and confidence are what matter most.

Genetics play the biggest role in determining the size and shape of your breasts.

Other factors include:

  • Weight. Fat plays a big part in breast tissue and density, so weight makes a difference.
  • Exercise. Pectoral exercises, like push-ups and bench presses, can build up the muscles behind your breast tissue. That doesn’t actually change the size of your breasts, but it can make them look perkier.
  • Breastfeeding and pregnancy. Hormonal changes can make your breasts swell during pregnancy, and they could get even bigger if you’re breastfeeding.

As your body goes through natural changes, so will your breasts.

You may notice that your breast size fluctuates throughout the month. This is usually tied to where you are in your menstrual cycle.

For example, many people find their breasts swell in the days leading up to menstruation.

You may also discover that your breasts settle into a new size or shape after pregnancy or breastfeeding.

Although some people return to their prepregnancy size, it’s common to experience lasting changes.

Your breasts are partly composed of fatty tissue, so any increase or decrease in body weight could also affect breast size.

Having more fat in your body could make for larger breasts, while less fat can mean smaller breasts.

Breast tissue also tends to sag over time, so you may notice the size and overall shape of your breasts change as you age.

You may have seen headlines claiming that larger breasts carry a greater risk for breast cancer, but that conclusion is pretty misleading.

A closer look reveals that having an increased risk for breast cancer is tied to things like genetic history, weight, and estrogen levels, rather than having a specific breast size.

Scientists haven’t found a definitive link between breast size and breast cancer.

There are a number of health conditions that can affect your breasts, including cysts, inflammation (mastitis), and skin conditions like eczema and acne.

These conditions are also linked to other risk factors like genetics and hormones — not breast size.

However, people who have large, heavy breasts may experience some unwanted side effects as a result.

Larger breasts may cause pain in the shoulders, neck, and back, as well as headaches, shortness of breath, and issues with posture.

Want smaller or bigger breasts? You could consider reduction or augmentation.

If you want reduction

If you want smaller breasts, you can look into getting breast reduction.

A plastic surgeon will remove extra tissue, fat, and skin to create a smaller bust.

You can start the process by reaching out to a plastic surgeon through the American Society of Plastic Surgeons or The American Board of Plastic Surgery.

Your surgeon will schedule a consultation to examine your breasts, evaluate whether you’re healthy enough for surgery, and determine if reduction is the right procedure for you.

If you want augmentation

If you want bigger breasts, you can look into getting breast augmentation, also known as getting implants or a “boob job.”

A plastic surgeon will add to the size of your breasts by inserting artificial implants or transferring fat from another area of your body.

As with any other surgical procedure, it’s important to have a skilled, certified surgeon perform your augmentation.

You can find potential candidates through the American Society of Plastic Surgeons or The American Board of Plastic Surgery. Once you have a surgeon in mind, read through their patient reviews.

You should also schedule a consultation with the surgeon before moving forward with the procedure. This will allow you to ask any questions you have and make sure you’re comfortable with them.

When it comes to your health and well-being, fitting into the average range of breast size isn’t as important as fitting into your individual comfort level.

You might be perfectly happy with the size of your breasts, regardless of how they measure up to others.

You can also explore different clothing styles, bra types, and even makeup to change the look of your breasts and boost your confidence.

Whether you want to call them your boobies, tits, or give them their own nicknames, like Thelma and Louise, your breasts are yours to embrace.


Maisha Z. Johnson is a writer and advocate for survivors of violence, people of color, and LGBTQ+ communities. She lives with chronic illness and believes in honoring each person’s unique path to healing. Find Maisha on her website, Facebook, and Twitter.