Bra sizing: How to measure your bra size

Comfortable, supportive and non-intrusive. A bra that fits well feels like a second skin.

At Triumph, we pride ourselves on making exceptional lingerie that works with your everyday. So, whether you’re looking for a bra that makes you feel comfortable like a lazy Sunday morning or one that doesn’t hold you back on your busiest days, we believe that everyone deserves to find a great fit. No excuses or shortcuts.

That’s why we’ve put together this bra fitting guide. Featuring step-by-step instructions and a calculator, this guide will help you discover your bra size.

We are the experts, and we’re here to help you find your perfect fit and determine the right bra size for your body.

How do I calculate my bra size?

When it comes to working out what bra size you are, you’ll need to get two bra measurements: your band size and your cup size.

You can work out these measurements by following the steps below:

1. Remove your bra and stand up straight.
2. To get your band size, measure around your body - you can ask a friend to help - just under the bust. You should hold the measuring tape quite tightly, but it should still be comfortable and allow you to breathe normally.
3. Read the number from the tape measure and round up or down to the nearest multiple of two for your UK band size e.g. 34, 36, 38 etc. (the measurement should be in inches).
4. Next, measure the widest part of your bust, keeping the tape fairly loose to avoid compressing your chest and influencing the measurement. Aim to keep the tape the same height across your bust and back.
5. Use this measurement to work out your cup size.
6. Take both bra measurements and add them to our bra size calculator to find your ideal bra size.

Alternatively, you can visit your nearest Triumph store for a professional in-person bra fitting to determine your band and cup size.

If you need to convert your UK bra size, our bra size chart has the equivalent EU sizes so you can find the right fit wherever you go:

How can I measure my bra size at home?

Once you have your measurements and suggested size, the final step in finding a bra that fits comfortably is to try it on at home. You can then feel how each part fits with your body and see if the bra sizing is correct for you.

But how should a bra actually fit?

The band

This part of the bra provides the majority of the support, so getting the right fit is crucial. The band should fit firmly, parallel to the cups and sit at the same height all around your body. Check this in the mirror or ask a friend to help out. Making sure the band is level will improve the fit of your bra and minimise the risk of back pain from wearing the wrong size.

If the band rides up at the back, it’s could be too big - size down and see how the fit compares.

The straps

Straps are also key for support so you need to make sure they fit properly.

When you’re wearing a bra that fits, the straps should sit parallel or slightly V-shaped on the back. They should sit comfortably on your shoulders, secure but not tight.

If the straps are digging into your skin, your band is probably too big and not giving enough support. Try a smaller under-bust and bigger cup size to ensure the rest of your bra doesn’t become too tight. Conversely, if the straps are slipping down your shoulders, the under-bust band may be too small. Try a bigger under-bust size and a larger cup.

The cups

When you have the right cup size, the bra should fit around the contours of your breast, sitting flat against your ribs without digging in.

To check the fit of the cups, lean forward slightly, lift your breasts and position them comfortably into the cup. Your whole breast should fit into the cup without spilling over the top or sides. This applies even when wearing push-up or low-cut bras.

If you feel the underwire is digging into your skin, try going one cup size bigger, but keep the underbust size the same. If the under-bust band is curling up or standing away from the body, the cup is probably too small. Go up a cup size and keep the under bust size the same.

The bra bridge

The bra bridge is the part of the bra in the centre at the front that connects the two cups.

No matter what style of bra, the bridge should lie flat against the body.

If there is a gap between the bra bridge and your rib cage, or the bra bridge sits on top of your breasts, the cup size is likely too small. Try to go up a cup size, keeping the under bust size the same.

Every body is different.

These guidelines should help you with bra sizing at home, but there may be variations in how a bra fits your own body. Different styles of bra will also fit you better than others; an underwire bra may fit better than a[bralette|https://uk.triumph.com/bralette], or one of our t-shirt bras may suit your breast shape best. Try on different shapes and styles to find your perfect match.

What is my cup size?

Getting the right cup size is essential for finding a bra that fits and makes you feel comfortable and confident.

In bra sizing, cup size is represented by letters (A,B,C,D, etc.) and is determined by the fullest part of your breast.

While a C or D cup may seem bigger than a B cup, cup sizes have nothing to do with how ‘large’ or ‘small’ your breasts are; it’s informed by your band size. Someone who wears a 32 D may actually have smaller breasts than someone who wears a 36 B.

To get your cup size, subtract your band size from the measurement around the fullest part of your breasts. The difference between the two numbers will give you your size:

Again, different bras will fit your body differently, and you may find that you need a bigger or smaller cup size depending on your chosen style.

Your bra size will be individual to you. While some sizes will be more common, there are no ‘normal’ band, cup or bra measurements.

Bra size calculator

Use your measurements to find a bra that fits perfectly with our bra size calculator. You can also use this UK bra size calculator to find your sister size.

What makes our fuller cup bras so special?

Dynamic. Empowering. Our fuller cup range is all about everyday support.

We’ve designed a series of bras that give you a great fit, even at larger sizes. Offering up to a G cup, our fuller cup sizes do not compromise on comfort or style. Our fuller cup bras also include:

1. Adjustable straps that mould to your shoulders and support you throughout the day
2. 3-D Flexi Wire, engineered to adapt to your body
3. A soft under-bust band, designed to provide the extra support that you need

Additionally, our Beauty-Full collection of fuller cup bras provides support and style with a range of bras to suit every individual.