HOW DO I WORK OUT MY BRA SIZE? | Miss Mary of Sweden
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How long was it since you checked what bra size you actually have? There is a good chance you may have changed size since you last measured. Women change their bra size about 4-5 times during their adult life. Use our guide to measure your size in three easy steps.

Why should you check your bra size if your favourite bra still fits, even if you’ve had it for a few years? Bras adapt to your body, but over time they also lose their elasticity and change the circumference and support they once had when you bought them. Bras that have stretched give you the impression that you’re wearing a larger bra size than what the size label says. It can therefore be a good idea to check your bra size regularly. Maybe you’ll discover that you need to go up or down one or two sizes next time you buy a new bra. According to a British survey a few years ago, eight out of ten women wear the wrong size bra, most without being aware of it. The most common is a bra that is too loose or with a cup that is too small.

So, how do you measure your bra size? It's easy and takes just a few minutes. All you need is a tape measure and a bra.


1. Put on a bra you think fits well and that supports the bust without flattening it, with cups that fit the whole of the breasts without them spilling out.
2. Measure the circumference round your upper body under the bust. The measuring tape should be tight. This is important as most bras have elastic backs that will stretch over time.

This measure is taken to obtain the circumference of the bra. Find your measure in the blue field in the table below. You’ll find your bra circumference in the same column. Example: If you measure your circumference as 91 cm below the bust, then your bra size is 90.

Size Chart Panties & Swimwear
Band sizes:   70 75 80 85 90 95 100 105 110 115 120 125 130
Measure 1 (Below bust): (1) cm 68-72 73-77 78-82 83-87 88-92 93-97 98-102 103-107 108-112 113-117 118-122 123-127 128-132

3. Measure the circumference where the bust is at its biggest in volume. This is usually around nipple height. You should wear a bra that fits well here too.


4.  Look at the table below and find the column with your bra circumference from step 2. Look down the column until you find the measurement that contains the cup size measurement you obtained in step 3. Example: You measure 91 cm below the bust and 105.5 cm in circumference where the bust is at its biggest. Then you have size 90 B.

Size Chart Panties & Swimwear
Band sizes:   70 75 80 85 90 95 100 105 110 115 120 125 130
Measure 1 (Below bust): (1) cm 68-72 73-77 78-82 83-87 88-92 93-97 98-102 103-107 108-112 113-117 118-122 123-127 128-132
A-cup (2) cm 82-84 87-89 92-94 97-99 102-104 107-109 112-114 117-119 122-124 127-129 132-134 137-139 142-144
B-cup (2) cm 84-86 89-91 94-96 99-101 104-106 109-111 114-116 119-121 124-126 129-131 134-136 139-141 144-146
C-cup (2) cm 86-88 91-93 96-98 101-103 106-108 111-113 116-118 121-123 126-128 131-133 136-138 141-143 146-148
D-cup (2) cm 88-90 93-95 98-100 103-105 108-110 113-115 118-120 123-125 128-130 133-135 138-140 143-145 148-150
E-cup (2) cm 90-93 95-98 100-103 105-108 110-113 115-118 120-123 125-128 130-133 135-138 140-143 145-148 150-153
F-cup (2) cm 93-96 98-101 103-106 108-111 113-116 118-121 123-126 128-131 133-136 138-141 143-146 148-151 153-156
G-cup (2) cm 96-99 101-104 106-109 111-114 116-119 121-124 126-129 131-134 136-139 141-144 146-149 151-154 156-159
H-cup (2) cm 99-103 104-108 109-113 114-118 119-123 124-128 129-133 134-138 139-143 144-148 149-153 154-158 159-163
I-cup (2) cm 103-107 108-112 113-117 118-122 123-127 128-132 133-137 138-142 143-147 148-152 153-157 158-162 163-167
J-cup (2) cm 107-111 112-116 117-121 122-126 127-131 132-136 137-141 142-146 147-151 152-156 157-161 162-166 167-171

The size chart gives an indication of what size you have. It works for most women but is not the whole truth. For example, the bra you are wearing when you measure will affect the size you come up with. If, for example, it doesn’t gather the breasts but lets them ‘hang naturally’, you will get a smaller size when you measure. So, bear in mind the fit and silhouette of the bra you are wearing when you measure.

After working out your size and trying a bra in that size, if you don’t think it fits well, go for the size you were wearing before if you think that fits better.

When you put on the bra, look in the mirror to see what it looks like. The whole breasts should fit into and fill the cups. The breasts should not spill out over the edges of the cups and the cups shouldn’t crease or be too loose. The underwire should fit tightly against the body and the sternum. It should never lie on top, then the cup is too shallow. It should not stick into the breast either, for example at the side, then the cup is too small. The shoulder straps should be shortened so you can get a finger between the strap and the shoulder. The band should be shortened so you can fit a finger between the strap and the shoulder. The back should be tight against the body but not so tight as to be uncomfortable or so you can’t breathe. If you pull the back of the bra in the middle, you should be able to pull it out about 5 cm from the body: then the bra is tight enough. For more information on how the bra should fit well, please read our article on the perfect fit here.

Breasts are individual. They are different distances apart and have different shapes. Some are narrow while others are wide, their fullness is distributed differently, some are round, some are teardrop shaped, and others lack any fullness. All this affects not only size but also the bra model that suits you. Some bra models are created for busts that need extra lift, some for those that lack firmness at the top and others for busts that need to be centred. Some models look better in larger cup sizes, while for others it’s the other way round.

Almost all women have different size breasts. When measuring, the tape does not take into consideration if one breast is larger than the other; it only works out an average for the two breasts. This can cause one cup to be too small and the other too big if there is a big difference in size. 


Patricia Twomey

Best guide to finding correct fitting size bra I have ever found. Thank you.

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