Without the help of our bra-size calculator below, finding out (and updating) your bra size can be a time-consuming and downright annoying thing to have to do. There are loads of great places you can visit to get your bra fitted (and I do venture afield, as you'll see below), but the truth is that it's super important to keep checking. Our bodies change fast (weight can fluctuate and our figures shift all the time), and wearing the wrong size bra can be rather damaging to your breast tissue. So although we would always recommend getting fitted properly, it is a great idea to be able to scope out your own bra size from home until you can fit the time in your schedule to get it done properly. That way, you can be on top of things when you're too busy to visit a lingerie department every six months.
Shop our Favourite Bras:
1. M&S Flexifit™ Wired Full-Cup T-Shirt Bra, £16
2. Sloggi Zero Feel 2.0 Stretch-Woven Bralette, £40
3. John Lewis AND/ORWren Non Padded Balcony Bra, £30
4. Rosie Rib
Lace Wired Full Cup Lounge Bra, £22
5. Wonderbra Ultimate Strapless Bra, £39
Why Do I Need a Bra-Size Calculator?
The first thing you'll learn? You've probably been wearing the wrong bra size for a long, long time. But don't worry—you're not alone in that mistake. It's incredibly common for people to assume that they have bigger backs than they actually do (or be scared of having a larger cup size for the fear that it will limit their underwear options). Here's where we step in to help.
To get some expert intel, I headed to both Marks and Spencer and Rigby Peller. The latter is an old-school underwear shop that has provided undergarments to British royalty and works very differently from other stores. Instead of measuring you, the bra fitters work by sight. They just look at your chest and work out which size you are. Both Rigby Peller and M&S came back with a 34D. Now, while just knowing someone's bra size from looking at their chest does seem like a sort of superpower every breast owner should have, alas, it's not something we can all possess, which is why I got thinking about a bra-size calculator.
What Are the Benefits of Our Bra-Size Calculator?
Although you can always opt for an in-store measure, our bra-size calculator is an easy way for everyone to work out their own bra size at home without having to step foot in a store should they not wish to or simply not have the time to spare. Keep scrolling for our guide on how to find out your correct bra size, and you can thank me later.
How to Use Our Bra-Size Calculator at Home
Step 1: Measure Your Band
To measure around the band part of your bust, which is directly underneath your breasts, make sure you have a soft tape measure to hand, place it flat against your skin, and draw it around your torso. Keep as close to under your bust as possible. Once you've done that, note down the number in inches.
Step 2: Measure Your Bust
Once you've done the band, then you want to measure the fullest part of your bust. Gently take the tape measure and measure it in inches as well.
Step 3: Work Out Your Cup Size
Then comes the slightly tricky bit: To work out what your cup size is, you want to subtract your band size from your bust size. From the difference between the two sizes, you can work out your cup. If the difference is less than 1, then it's AA; 1 means A; 2 means B; 3 means C; 4 means D; 5 means DD; and so on.
You'll still need your band measurement to give you the number preceding the letter. For example, if your band size is 34 but your bust size is 37, then your bra size is 34C (difference of 3, again, means it's a C-cup). Of course, it's worth mentioning that bras can fit differently according to different brands, but now you have the basic tools to work out your correct size.
If you need more guidance, I also spoke to bra-fit expert Julia Mercer from M&S, who gave me some further insights so that if you ever want to know how to find the right size, you'll be in no doubt. First off, Mercer said that as the average bust size of women in the UK is growing (34B to a 36D/36DD in the last decade), "it's become more important than ever to wear a bra for both comfort and support."
Mercer also said, reassuringly, that you should "never be alarmed if you have to go up a cup size," as this will not only help you look more in proportion but will also help your posture. And the best way to check if your bra is fitting correctly? "Lift up your arms, twist your body, and the bra will fit perfectly in place," she advises. For more help, keep scrolling for a bra-fitting checklist.
5 Key Checks for the Perfect Bra Fit:
1. Under-Band: This should be parallel to the floor and secure enough that only two fingers can fit under the elastic.
2. Centre Front: Should sit completely flat against the sternum.
3. Side Wire: Make sure this is flat against the rib cage and never digging into the breast tissue.
4. Cup Capacity: Breasts should sit fully into the cup without any spillage.
5. Straps: These should be adjusted to just fit two fingers on top of each other, which will give the right pressure for your shoulder.
Now that you've got all of the tips on calculating your own bra size, it's time to shop! See my favourite bras to buy now.
Shop the Best Bras for All Sizes:
- T-Shirt Bras
- Non-Padded Bras
- Black Bras
- Strapless Bras
- DD+ Bras
- Pretty Bras
1. T-Shirt Bras
Customer Review: "While pricier than other brands, this bra is worth every penny. It's true to size, well constructed and has smooth contours. The lace around the band is a lovely feminine touch on an otherwise very practical, every-day T-shirt bra. The straps are supportive without being wide and ugly, and they don't cut in—even by the end of the day with a fuller bust (36E). Highly recommended."
Pros:
- Convertible straps to adjust to different styles of clothing.
- Binding along neck the edge for a finish that sits flat against the skin.
- Ultra-smooth outer cups for a natural shape under clothing.
- Mesh underband for full, yet comfortable support.
- Extended size range (to an F cup).
Cons:
- Limited colour selection.
- Could offer more side coverage.
Customer Review: "Comfort is excellent with A+ support. Smooth hugging shape and feel. Glad I chose this bra."
Pros:
- Seamless design for invisibility underneath clothing.
- Made with wide straps and extra side-material for full coverage.
- Wireless and label-free to prevent underwear lines.
- Brushed finish for maximum comfort.
- Selection of colours.
Cons:
- Not the prettiest.
- No white colour way.
Customer Review: "Lovely soft, comfortable bra that fits well. Cups are smooth and the side panels are deep and don't cut in. Tiny bit of lace decoration between the cups and a ditzy bow. A great everyday wear."
Pros:
- Varied range of nude shades to adapt to skin tone.
- Made with Flexifit™ technology for a stretch that moves with the body.
- Full-coverage cups for maximum support.
- A lightweight, breathable material for comfort.
- Reasonably priced.
Cons:
- Some customers say the fit is slightly smaller than usual.
Customer Review: "Firstly, this bra doesn’t run large. It runs quite small. I wear a 30F in multiple brands but had to size up to a 30G in this bra. Secondly, this bra is supportive but also very, very, very comfortable. I have an issue with the gore (piece of fabric that runs across the middle below the cups) on many bras curling under and cutting into me despite correct sizing. This bra is cut higher in that area and does not curl under. I finally found it. It’s the one!"
Pros:
- Fitted with smooth spacer cups to be invisible under clothing.
- Thin padding on bra cups to avoid unwanted volume increase.
- Natural neckline to fit seamlessly under clothing.
- Underwired cups for complete support.
Cons:
- A higher priced option.
- Some customers report a smaller fit.
Customer Review: "Having bought from Oola before, I knew for sure that this bra would provide plenty of comfort whilst still looking amazing. I bought this alongside the Control High Waist Thong and needless to say both are fantastic. The microfibre used feels great on the skin, and it's clear that comfort was in mind with this."
Pros:
- Made with a soft microfibre material for long-lasting comfort.
- Underwired cups for optimum support.
- 4 hook and eye closure to tailor the fit and minimise skin irritation.
- Fully adjustable straps to fit under clothing.
- Designed specifically for DD+ sizes with bands of 38 and up—a notoriously under catered to size range.
Cons:
- Not available in A-C sizes or bands under 38 inches.
2. Non-Padded Bras
Customer Review: "I purchased this bra based on advice from a John Lewis sales assistant and online reviews—I'm so glad I did. After wearing it for a few days I purchased another one but in the different colour. It's really comfortable, gives great shape and support, and the design is very attractive. Freya bras were recommended to me in-store; I had explained that I can experience discomfort with some bras where the middle section which sits on the breastbone comes up too high and digs in. The assistant knew exactly what I meant and immediately recommended Freya whilst also confirming my size. I'm really pleased."
Pros:
- Made with a semi-sheer material for breathability.
- Fully-adjustable straps to prevent slipping.
- Rigid yet soft underwire for secure and comfortable support.
- Flattering plunge neckline.
Cons:
- Limited colour selection.
Customer Review: "I can't believe how comfortable these bras are. They are so supportive and give a nice shape. They are a bit pricey [compared to high street] but well worth it. I now own several colours."
Pros:
- Unlined seamless cups for natural shaping under clothing.
- Made with moulded stretch brushed lace for a comfortable fit.
- Multi-functional J Hook to allow racerback styling.
- C-G sizing.
Cons:
- Limited colour selection.
- Lace can be more delicate when wearing and washing.
Customer Review: "I have been looking for a good bra for long time since my previous bra company went seriously downhill! I wanted the following: Non-padded, strong cup material to hold me up and in flush so it would sit seamlessly under my clothes, side support cups [that are] high enough so I have no spillage, wide enough straps and enough hooks for back support. This bra certainly does all of the above!"
Pros:
- Made with three-piece cups for forward projection and side-support.
- Fitted with a stretch band along the neck edge for a tailored fit.
- Padded hook and eye fastening for comfort.
Cons:
- Hand wash is recommended.
Customer Review: "Excellent bra. Great quality and style. Attention to detail outstanding. Reluctantly returned as cup too big but the smaller size was perfect."
Pros:
- Made with a firm mesh material and underwiring for support.
- Full coverage cups for a seamless finish underclothing.
- Adjustable straps for comfort.
Cons:
- Some customers report a smaller fit than usual.
- Those with sensitive skin may find this material itchy or irritating.
Customer Review: "Looks great and a really good fit. Really pleased with my purchase. And/Or is now my favourite for lingerie."
Pros:
- High apex styles for ample support.
- Made with a "cut and sew" design to lift and support.
- Non-padded cups for a natural look under clothes.
Cons:
- Straps have limited adjustment room compared to other styles.
3. Black Bras
Customer Review: "Delighted to see a new style full cup bra, I’m a 32GG, fits perfectly for me, good shape and support round the cups, feels lightweight on."
Pros:
- Made with Natural Lift™ innovation to lift and define bust.
- Unpadded cups for subtle support.
- Full cups for comfort.
- Plunge neckline for a flattering finish.
Cons:
- The thick lace design may show through clothing.
Customer Reviews: "I love this bra. I’m a 34DD/36C and find this bra to be very comfortable and flattering. While it doesn’t have any actual support, I still feel supported in it. It’s pretty, flattering, and comfortable!"
Pros:
- Barely-there design to fit seamlessly under clothes.
- Adjustable shoulder straps for comfortable support.
- Side boning for a structured and supportive fit.
- Lots of colours.
Cons:
- Minimal support.
Customer Review: "I love this bra so much! It’s very comfortable and my chest just sits in the cups like dough. If you like a little support but ultimate comfort and can’t wear bralettes because you have bigger boobs, THIS IS THE ONE!"
Pros:
- Made with a mesh material for all-day comfort.
- Seamless raw edge finish for invisibility under clothing.
- Featuring smoothing microfibre wings and sheer unlined cups.
- Diverse selection of "nude" shades.
Cons:
- Some customers say sizing is different compared to other brands they wear.
Customer Review: "Perfect fit and very comfortable bra. Looks pretty and gives a good shape, and it's not too expensive either."
Pros:
- Full-cups for maximum coverage.
- Thin padding for a smooth look under clothing.
- Fitted with an elasticated underband for a comfortable fit.
Cons:
- Some customers report a smaller fit than usual.
- Unlike other styles in the range, this bra only comes in sizes A-E.
4. Strapless Bras
Customer Review: "Provides really good support and shape and is relatively comfortable. Comes at a higher price than some but overall I think it's worth it."
Pros:
- Foam cups to create a "push-up" effect.
- Hand-shape technology to ensure support.
- Made with silicone dot technology to keep the bra in place.
- Smooth satin fabric for comfortability against skin and a sleek finish under clothes.
- Extended size range.
Cons:
- Is quite large so may peek out from certain cuts of clothing.
Customer Review: "After trying on about 30 bras, this one was hands down the winner. It holds comfortably, stays in place, the padding at the bottom is soft, and somehow the sticky parts stay put and don't irritate my skin, even with a lot of movement. The shape is natural for me. I went out and bought some cute strappy sleeveless shirts to celebrate this find."
Pros:
- Seam-free contour cups for a smooth look under clothing.
- Lightly padded to support without adding unwanted volume.
- Cushioned underband for comfort.
- Fitted with detachable straps.
- Natural-looking shape.
Cons:
- Some customers reported it was too tight across the back.
Customer Review: "I love all of the Skims bandeaus! They all fit great and they are so flattering. I wear them as cute crop tops in the summer. For reference, I am a 34C and I have both large and medium sizes. The large is just a little bit more coverage but the medium fits great too, I like how the medium is a little tighter. You can go either way!"
Pros:
- Stretchy fabric to mould to the body and bust.
- Made with a no-cut design that offers subtle support without digging.
- Extremely comfortable to wear.
- Extensive colour range.
Cons:
- Some customers report that is isn't as supportive as they would like.
- Lacks definition.
Customer Review: "As per the description, this really is a soft feel bra but with plenty of support. I'm a 32DD and loved the shape of the cups and the overall look. It's a nice looking bra that does exactly what it should. I felt it was good value for money and I would recommend it."
Pros:
- Soft-wired cups to avoid skin irritation.
- Invisible wiring for a seamless fit under clothes.
- Detachable straps to suit all styling options.
Cons:
- Some customers reported that the straps are hard to remove in a hurry.
Customer Review: "I was skeptical at first wondering if it would do it's job, but I was surprised as it held me up all evening and didn't drop down once, so thank you."
Pros:
- Sewn inner cups to prevent slipping.
- Features a wide hook-and-eye for extra support.
- Fully adjustable and detachable straps to suit styling options.
Cons:
- Some customers reported a large cup fit than usual.
5. DD+ Bras
Customer Review: "Seams and stitching are excellent, fabric is as pictured and soft against skin. Lovely shape and stands up to washing well. I wash at 40 degrees in the machine inside a string bag and line dry and this seems to be working well."
Pros:
- Features a wider neckline to flatter fuller busts.
- Non-padded cups to avoid unwanted volume.
- Added stretch for comfort.
- Thicker hook and eye fasting for support.
- Expensive-looking finish.
Cons:
- The seams may show through close-fitting clothing.
Customer Review: "After a brilliant bra fitting service and recommendation, this bra is the most supportive, figure-enhancing and comfortable bra I have ever had. in fact I went back the following day and bought a second one."
Pros:
- Made with a three-piece cup for optimum lifting.
- Fitted with an opaque wing for additional support.
- Fully adjustable straps to prevent slippage.
Cons:
- Some customers report the wiring begins to rub after wearing for longer periods.
Customer Review: "Beautifully supportive and comfortable bra. So good I bought black after buying white."
Pros:
- Laminated side cups for forward projection and support.
- Stretch mesh with increased LYCRA® content for comfort.
- Adjustable straps to prevent strap slippage.
Cons:
- Only available in two colours.
Customer Review: "True to size, well made and very supportive. Lovely subtle colour too."
Pros:
- Made with stabiliser-lined bottom cups to provide support.
- Features an inner side sling for comfort.
- Plunge neckline to fit seamlessly under low-cut clothing.
Cons:
- Colour isn't the most versatile.
Customer Review: "I ordered six strapless bras all in the same size but all different manufacturers. Surprisingly they all fitted and were consistent in their sizing and this is the one I chose to keep. I’ve now worn this bra twice and for a full day on each occasion and am thrilled at how comfortable it is. I’m a 34F and strapless bras are rarely super comfy but I can honestly say I forgot I was wearing it. It has a deep band with four fasteners and I do need assistance with doing it up but once on it stays put and it doesn’t have the rubberised bands around the rib cage. The cups are full, it’s only lightly padded and appears seamless under a clingy top. I’m thrilled with it and may well get the black option too."
Pros:
- Padded underwire for a smooth look under clothing.
- Multi-way straps to suit different necklines.
- Comes in band sizes 30-42.
Cons:
- Some customers report that the sizing is smaller than usual.
- Limited colour range.
6. Pretty Bras
Customer Review: "I treated myself to a Dora Larsen lingerie set last year and it's by far my favourite. The colours are gorgeous—hand wash or wash on cool and they really last."
Pros:
- Contrasting adjustable satin shoulder straps for support.
- Elasticated underband for comfort.
- Features an elegant sheer floral-lace design.
Cons:
- Higher price point.
Customer Review: "I have small boobs so really don't need big, supportive bras. Other Stories's triangles are pretty and my favourite to wear."
Pros:
- Semi-sheer material.
- Adjustable straps to prevent slippage.
Cons:
- No support.
Customer Reviews: "The prettiest bra - so I bought the matching thong! Gorgeous colour and fits perfectly (I’m a 32C and size small). Can UO do this style in other colours too please?!"
Pros:
- Floral print with lace trim that looks high end.
- Features underwire cups for support.
- Slight padding for additional shape.
Cons:
- Print may shine through from underneath light clothing.
Customer Reviews: "Fleur Du Mal lingerie is the ultimate luxury!"
Pros:
- Pink floral design with subtle scalloped-edge.
- High-quality
Cons:
- Higher price point.
- Detailing may not be practical for wearing underneath clothing.
Customer Review: "Quality product very comfortable fit and excellent appearance. This brand is now my new favourite."
Pros:
- Made from airy tulle.
- Intricate embroidery that looks very premium.
- Features embellishments between cups.
Cons:
- Plunge bras can be prone to overspill.
This piece was published at an earlier date and has been updated.
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