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How to measure your bra size at home in 4 simple steps

You'll need a tape measure and five minutes

how to measure your bra size
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Knowing how to measure your bra size should be something we're taught, right? But how often are we stuck looking at bras, strapless bras and sports bras online, not knowing which size we should plump for?

Odds are, unless you had an attentive parent who regularly took you to one of those slightly awkward bra fittings (that always ended in a sensible new t-shirt bra), your choice of size was not based on measurements – as it should be – but on the look, feel and potentially holding it up in front of the mirror. Which might work for kit such as gym leggings or workout shorts but a bra? Not so much.

Regardless of whether you’re a devout bra wearer or prefer to throw one on if and when you see fit, or if you prefer an underwired bra or a soft one, with statistics indicating that the majority of bra wearers are wearing the wrong size, it’s clear a little help could benefit us all.

That’s where we come in. There's more than enough conflicting information on the world wide web as is, so we thought it best to get in touch with a few bra experts to find out how to measure your bra size the right way. We’ve gone and got the lowdown and we’re willing to share.

Why is it important to have a well-fitted bra?

Apart from being way more comfortable to wear, having a well-fitted bra is also a matter of health, and wearing the wrong bra size can contribute to back, shoulder and neck pain.

CEO and founder of Pour Moi Ltd, Michael Thomson explained further; 'Wearing the wrong size bra can lead to a range of issues, from poor posture and pain to sagging. With a 4cm range of sway in every direction, even something as gentle as walking up the stairs without a bra could be enough to stretch your delicate skin.'

Ominous right? Not to worry, you’ll soon have everything you need to arm yourself with just the bra for you.

How often should you get measured for a bra?

More often than you think, that’s for sure! There’s no exact date but most lingerie brands tend to suggest getting measured around the 6-month mark or when you’re looking to buy a new bra.

Marks & Spencer recommends getting fitted as regularly as every 6-12 months to take into account the natural fluctuation of breasts, be that from weight changes or hormonal changes, particularly during pregnancy.

Looks like it’s high time we got measuring…

How to measure bra size

Quite a few lingerie brands, Beija London and Marks & Spencer included, no longer use a tape measure. To them, the best way to measure bra size is by eye, something that despite being quite common these days, still seems rather impressive.

Whether you’re in-store or online, their expert fitters have the ability to look you over whilst you’re wearing your usual bra or one you feel particularly comfortable in and send you on your way, 20 minutes later, equipped with your correct bra size.

At Freya, things are done quite similarly with fit specialists rarely picking up a tape measure to do any measuring. However, thanks to an increased need for virtual fittings during lockdown, they decided to look into the most accurate way to measure bra size with a tape measure and, we have to say, we’re glad they did.

Suzanne Pentland, one such fit specialist at Freya, kindly abandoned her supernatural sizing-up abilities for us mere mortals, and the result is a simple four-step method to measure your bra size when all you have at your disposal is a tape measure.

How to measure your bra size with a tape measure

Before we get started, you’ll want to make sure you’re wearing a simple non-padded bra so that your boobs are in the right position and that you have a soft tape measure on hand.

1. Measure your band size

  • Place the measuring tape around your ribcage, right underneath the band of your bra.
  • Make sure it is pulled tight but is not uncomfortable and that the tape is level.
  • Make a note of how many inches you are.
  • If you land on an even number, this is your band size.
  • If you land on an odd number, you’ll want to round up or round down to the nearest even number based on your build.
  • Round down if you’re softer around the band and round up if you're leaner and don’t have much give around the band. This is then your band size.

    2. Measure your cup size

    • Place the measuring tape around the fullest part of your bust.
    • You won’t need to pull the tape particularly tight for this measurement it just needs to sit flat, but you’ll still want to make sure it’s level.
    • Make a note of how many inches you are.
    • This is your cup size.

      3. Calculate your cup

      Don’t worry, this won’t require you to go back in time and recall all the mathematics skills you supposedly took in at school. Simple subtraction will do.

      • Minus your band size from your cup size and make a note of this value.
      • This difference indicates your cup
        how to measure bra size

        4. Determine your bra size

        • Finally, take your band size and your cup and put them together to get your bra size.

              Just to make sure we’re all on the same page we’ve got an example to reinforce your newfound bra knowledge.

              If you measure your band size as 34 inches and your cup size as 37 inches, the difference between the two is 3 inches. This means you have a C cup, and your bra size is 34C.

              Voila! Done! And you didn’t even need to pull out your calculator to get there. Or at least we think you didn’t...no judgement either way.

              How to check if your bra fits properly

              We’re not done imparting wisdom just yet. We gathered some expert tips from the professionals on how to determine whether the bra you have on is the correct one for you.

              Band Fit

              “One of the most significant things to get right is the band size,” says Suzanne from Freya. “An incorrect band size has the potential to make the cups and wires less effective. A good band size will allow you to slide 2 fingers underneath the band at the back and have about an inch of give when you pull it away from your body.”

              The band should be horizontal all the way around and should fit you properly when secured on the last hook. As you wear and wash your bra, the fit will become looser, so you’ll want to move to the second hook to get a better fit and then finally to the tightest hook.

              Georgia Larsen, the founder of independently owned, conscious lingerie and sleepwear brand Dora Larsen, had this to say about band size.

              “It’s important for a bra to be fitting firm across your rib cage so you’re not relying too much on the straps to be supporting you. This is where a lot of people go wrong with fitting, they’re often wearing a band size too big as they assume this will make it more comfortable. But when you’re wearing a firm band size, it holds your boobs in place more easily, so you’re less reliant on the rest of the bra supporting you.”

              Cup Fit

              In terms of the cup, customer services manager Laura Franklin, at Bravissimo, says there are a few things worth noting.

              “You may notice the cups aren’t fitting you as they should be. Your cups may be too small, resulting in your boobs spilling out of your bra or the cups may be wrinkled or gaping which indicates your cups are too big.”

              Bridge Fit

              Other places to check are the bridge/gore of the bra, the piece connecting the two cups that lies across your chest bone at the front, and the wiring. Co-founder of lingerie and swimwear brand Beija London, Abbie Miranda, has a checklist of what to look for in your new boob hugging bestie.

              “Firstly, the wires at the centre front - also called the gore, should be sitting flush against your body. Not standing away and gaping. Secondly, and imperative to your health, the wire at the side towards your underarm should be behind all of your breast tissue. The underwire should not be sitting on your boob! Instead, you should have all of your breast tissue scooped in, in front of the wire.”

              Strap Fit

              Lastly, before deciding that your bra is the wrong fit check to see whether you’re using the straps correctly. “I think one of the most common errors people make in fitting is to not adjust their straps in the right position,” says Georgia.

              “If you leave them too long you can be misled into thinking you need a smaller bra, as you’ll have extra room in the top of the cup or the cup will seem baggy. But make them a bit tighter and the bra will fit you a lot better, and you’ll get an extra lift. The same applies if you’re wearing a bra you’re worried is too small (for example you might be double-boobing a bit at the neckline), just adjust the straps to be longer and it can make a big difference!”

              The straps should be tight enough to avoid them slipping off but not so tight that they feel uncomfortable or dig into your skin.

              Bra sister sizes

              It’s worth noting that a bra size that works for you in one brand may not be exactly the right fit in another. Something that sister sizes can help with.

              A sister size is the bra size that will give you the same cup volume but with a smaller or larger band size depending on your needs.

              how to measure bra size

              If the band of the bra you're trying in your usual bra size feels loose, try the size to the left of your current one and if the band feels tight try the size to the right of your current one.

              For example, if you're usually a 34C but the band feels loose, you'd try a 32D. But if the band feels tight, you'd try a 36B.

              Another scenario where you may want to use sister sizes is when a style you’re eyeing out isn’t available in your specific bra size. Trying your sister sizes may just lead to a comfortable fit in the bra of your dreams. Talk about family coming through for you!

              Bras to shop now

              How to measure for a sports bra

              Finding the right size sports bra is just as important as a regular bra. You’ll want to find one that can support you through the toughest of sessions and part of that involves nailing the correct fit. Something extra important if you’re someone with larger breasts and could use additional support.

              According to a University of Portsmouth study, unsupported breasts can move up to 14cm during vigorous or strenuous exercise. Experience this often enough, and you could be at risk of permanent damage to the Cooper's ligaments that help to hold your breasts in place. Even more reason to make sure you know how to pick the one for you.

              Unlike regular bras, where the choice is often between underwired, wireless or strapless, sports bras come in a range of different supports, so you can customise your fit.

              • Low support = best for Yoga and walking (most ideal for smaller cup sizes, AA–B)
              • Medium support = dancing, strength training, cycling, low-impact exercise (Pilates and Barre) and skiing
              • High support = best for running, aerobics and HIIT (most ideal for larger cup sizes, D+)

                Is sports bra size the same as normal bra size?

                Yessiree! BUT don’t get too excited just yet. It’s not always as straightforward as that. Depending on the brand and the amount of support offered, the sizing metrics may differ.

                Some brands or bras with greater support will be sized according to cup and band size, just like your regular bra, but other brands and bras generally offering low to medium support will use a scale from XS to XL+. This means you’ll then have to convert your bra size to its corresponding XS to XL+ size.

                Thankfully, almost every brand requiring you to do conversions will have a handy size chart just for this. Phew!

                How should a sports bra fit?

                The overall fit should be snug but not too tight. A well-fitting sports bra won’t mark your skin, cut off your circulation or restrict your breathing. It might sound silly but try jumping around a bit in your potential pick to make sure it’s comfortable, the band stays in place and you are able to move freely. You should feel supported and secure.

                Once you’ve got it good, remember what size works for you so you'll know for the next time you go to buy a bra from the same brand. Feel free to celebrate your success but maybe don’t get too attached to your new workout buddy. You may think you've found one for life, but sports bras should be replaced every 30 – 40 washes after they lose their elasticity.

                Sports bras to shop now

                Shop the bras we rate online

                Looking for something in particular? Look no further. No matter the occasion, your size or what stage of life you're in, there’s a bra out there for you!

                • Looking for a strapless bra, that’s just as supportive as one with straps, we’ve got an edit of the best strapless bras to hold you right.
                          • If you prefer a life sans bras, you may appreciate our selection of the best bralettes, that’ll give you the comfort you’re looking for but still provide support.

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