How to Choose the Right Bra Size

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 measurement.

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.

Still confused?

For the safest bet, opt for a wireless bra or bralette.

Whether you’re looking for a bra for yourself or for your partner, a wireless bra (be it a stretchy bralette or a tie up bikini style) is a great option when you’re unsure of sizes. This is because the supportive stretch fabric used in wireless bras fits a wide range of sizes, while a tie up style can be adjusted to fit your unique breasticals.

For stretchy styles, you can usually choose between sizes small to extra extra large. If you usually wear a smaller dress size up top, opt for a size small; if you wear a larger size go for a large or an extra large.

For one-size options, you can choose between One Size (8-16), One Size Queen (18 - 24) and One Size Curve (24 - 28).