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Understanding Bra Sizing

95% women don't understand bra sizing

In the years we have served our customers, bra sizing comes up again and again as something that women have been getting wrong. Knowledge of bra sizing is rare these days. Because women don't understand bra sizing, more often than not, they're wearing the wrong size bra. If you think about it, bra sizing isn't something that's taught to us. Unless you do research or get professionally measured, you will be relying on your shopping experience to inform you on your bra size. But relying on underwear brands to tell us what size we are is completely unreliable for 2 reasons. 1. Every brand has their own size charts. This means that you may be a 34C in one brand and a 32D in another. 2. Some brands do not carry larger cup sizes. So you may be a 32F, but because the brand doesn't carry a F cup, they fit you in a 34DD. The best way to ensure you're getting the right bra fit is to learn a few things about bra sizing.

What does a bra size tell you

What a bra size represents is your breast volume.

Lets look at 34 C as an example. The number element (34) is how much you measure around your rib cage. It is also called band size. The letter element (C) represents the different between the measurements of your rib cage and your breast at its fullest (measuring over the nipples and around the back). Every inch of difference is one cup size difference, starting with cup A. So if you measure 1 inch difference between the 2 measurements, then you're a cup A. 2 inches different, then you're a cup B. 3 inches different, then you're a cup C and so on.

What this means is that you have to take into account both elements (band size and cup size) to determine your boob size.

D cup doesn't mean you've got ginormous boobs

A 30D is not the same as a 36D. When you read the cup size in context of the band size, you have a better picture of breast volume. In the illustration below, the first line shows the same cup volume. As band size increases, cup sizes decrease. This is a representation of sister sizes. The sister sizes of a bra size are sizes that hold the same breast volume. For example, 30F and 34DD are both sister sizes of 32E. You may want to go for the smaller or bigger size, depending on the bra's fit.

On the second line, you can see how different a DD cup is at 30 inch band size and 38 inch band size.

On the third line, you see the difference in breast volume when the band size remains the same while the cup size increases.

Bra sizing is not static

Your cup size can not only change when you lose or gain weight, it can also change depending on the time of the month. Hormones that dictate your periods are make your breast bigger. The only way to be sure of bra sizing is to be professionally measured and you should get it done every 12 months. If you haven't been professionally measured or if you have been measured more than 12 months ago, there's a chance that you're wearing the wrong size bra.

You might be underestimating your cup size

More often than not, women think they're a smaller cup size than they are. As many high street lingerie brands do not offer larger cup sizes, a lot of women are buying bras that are too big around their rib cage but too small in the cup. The problem with this is that the bra doesn't fit you properly. For InvisiBra, if you're buying without using a bra size convertor then chances are you might get the wrong size.

How does Invisibra's bra sizing work?

If you don't have time to get professionally measured, you should follow our guide on how to measure bra size and use our bra size calculator to work out your bra size as well as InvisiBra size. InvisiBra is a backless bra, so our bra sizing is different to normal bras. Because there's no back strap, our sizes are in A, B, C, D. But as mentioned above, the band size element does still matter, as we need to first work out your breast volume, then match you to the right InvisiBra size.

To illustrate how InvisiBra's sizing works, you can refer to the top of the page where we fitted InvisiBras onto our participants.

How to boost your cup size

If you're a cup A or B and you want to go for fuller boobs, then go for our backless push up bras which are padded at the base of the cup to give you a boost. You could also try out some of our suggestions on how to boost your cup size naturally.

InvisiBra does work for bigger cup sizes

As you can see, we fitted women with 32F, 34 E, 36D in Invisibra's size D. Whether InvisiBra works for you depends on your band size and the level of firmness of your boobs. For cup size F, your band size needs to be 34 inches or below for InvisiBra to work. For cup size G, your band size needs to be 30 inches or below. InvisiBra’s sizing works differently to normal bras because our bras are backless. Without shoulder and back straps, our D cup can fit anything from 28G to 38DD.

For InvisiBra to work for bigger breast sizes, it's essential that your breasts are firm and have not lost too much elasticity. You can lose breast elasticity if you've lost a lot of weight or gone through multiple pregnancies. If you would describe your breasts as "saggy", then InvisiBra will not offer you much support.

If you are a bigger size, ensure to go for our lifting backless bras which will offer you maximum lift and support.

Ultimately, bra sizing is not a science but an art form. The best way to find out whether InvisiBra will work for you is to order one. Our bra cups come covered with a layer of plastic film to enable you to test for size, as long as you do not remove the plastic film, you can return the item.

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