How To Choose the Right Bra Size

Chances, are, by now, you think you know your bra size. But when did you last get measured, or measure yourself?

We've all heard that up to 90% of women are wearing the wrong size, which, given the implied health risks, is a little worrying.

Even a little weight loss or gain can affect which size you are, and with very, very few people remaining the same size and shape for their entire adult lives, chances are you could have changed and not even noticed. We recommend checking your bra size at least once a year.

Luckily, you don’t need a professional lingerista to burst into your house, waving a tape measure: we’ve got some expert top tips right here to allow you to do it yourself, simply and easily.

Video: How to Check the Fit of Your Bra

If your bra doesn't feel quite right, it might not fit the way it's supposed to. The Lovehoney experts share their tips for checking that your bra fits properly.

How to Find Your Bra Size

Before you start, you’ll need to grab your most comfortable bra (as chances are, this is the one that fits you best), a soft tape measure, and a mirror. Make sure that the bra doesn't have any extra padding, as this could falsely affect the reading.

  1. Standing in front of the mirror whilst wearing the bra, pass the measuring tape around your back and pull it firmly (but not tight!) against the skin just beneath your bust, where the underwiring usually sits. Check the measurement in inches, and, if it’s an odd number, round it up to the next even number. This is your band size.

  2. Next, move the tape measure up to the fullest part of your bust, keeping it against your body without it digging in, and read the measurement in inches. This is the overbust measurement.

  3. Now it’s time for the maths. Take the band size measurement away from the overbust measurement, and whatever the difference is will tell you your cup size. Every inch difference between underbust and bust measurements is an extra cup size; so, for example, if you measure 36 inches under the bust, and 40 inches around, you’re left with a size difference of 4 inches, which makes you a 36DD.

Simple, right?

Non-cup sized Bras

Sometimes, you may come across bras (particularly in sets) that are sized by dress size, or Small, Medium, or Large rather than cups sizes, and this can get a little confusing.

On Lovehoney, all of these bras should have a brand size chart featured on the page which tells you the equivalent dress size, but not necessarily the cup size.

Sister sizes

The volume that a bra can contain (i.e. the sheer amount of boob) is proportional to the underbust size, meaning that when you increase the underbust, you're increasing the size of the cup, even if you choose the same cup size.

So let's say you are a 34B. If you increase the underbust size of your bra to the next width up (a 36) and decrease the cup by one size (an A), then you have what is known as one of your "sister sizes" - that is, a bra with essentially the same volume as your true size.

This does require a degree of common sense, however: technically, a 30G bra would have the same volume as a 44A, but as most bras only come with 3 hook-and-eye positions on the back fastening, it's unlikely you'd be able to get the best fit beneath the bust. Generally speaking, you can go up to two sister sizes in either direction.

More Sexual Happiness Advice

You can never know enough about sex, right? Join us on our sexploration journey via the thriving Lovehoney forum, our weekly Sexual Happiness podcast and our blog.

Lovehoney Forum

Sexual Happiness Podcast

Lovehoney blog