How To Measure Bra Size - InvisiBra
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How To Measure Bra Size

Why is it important to measure bra size?

Because too many women don’t know their true bra size. Therefore, if you’re looking to buy a backless bra from us, then it’s essential that you follow our guide on how to measure bra size to get your true bra size. Also, InvisiBra works best if it fits perfectly or a little small. If you’re a B and end up getting a C by mistake, chances are, you won’t get much lift, shape or support. Why? Because a backless bra in too big of a size would swamp your boobs. Stick on bra cups that are too big would be positioned really close together (because they’re too big for your chest), and you’ll get zero cleavage and pancake boobs.

Apart from InvisiBra, getting your other bras in the right size is essential for comfort and fit. If any of these apply to you, then you’re probably wearing the wrong size bra and should therefore get measuring right away!

  • Bra band rides up your back
  • Bra band feels too tight
  • Shoulder straps dig in
  • Shoulder straps fall off
  • Centre of bra doesn’t lie flat against chest
  • Boobs bulging out of cups
  • Boobs don’t fill cups
how to measure bra size

When to measure bra size

Now! Almost 95% of women are wearing the wrong size bra, which can cause a plethora of health problems like back, shoulder and neck pain. Yikes! Rather than that, why not be the smart 5% who’s got her boobs the support it deserves. Lingerie isn’t cheap, and for that reason, if you’re going to splash on it, you might as well get it right.

You should also measure bra size every 12 months because bra sizing can be volatile. Gaining and losing weight, pregnancies, hormones, birth control pills, menopause and age are all factors that affect your bra size. If you have never been professionally measured or measured yourself, then now is the time to find out what your true bra size is.

How do I measure bra size?

First of all, you need a tape measure. Our calculator uses inches, so get one that has inches on it. All you need is a few minutes and 5 measurements. Then put it into our bra size calculator to find out what your true bra size is. Measure yourself in front of a mirror or get a friend or partner to measure you. And babe, go natural. Don’t wear a bra while measuring.

Measure bra size

1. Underbust

Snug underbust (measurement 1): Measure your underbust (line 1). Hold the measuring tape parallel to the ground and exhale. The tape should be snug, tight enough that it doesn’t move, but not too tight that it digs into your skin.

Tight underbust (measurement 2): Measure your underbust again, but this time, pull the tape as tight as possible & exhale.

2. Standing bust

Measure around the fullest part of your breasts (line 2), make sure the tape goes over your nipples and is parallel to the ground.

3. Leading bust

Lean forward so that your upper body is parallel to the ground and your breasts are hanging. Measure around the body and the fullest part of your breasts. Keep the tape perpendicular to the ground.

4. Lying bust

Lie down on the ground and let your breasts fall naturally to the side. Measure around the body and the fullest part of your breasts, making sure that the tape is as straight as possible.


Please enter your measurements to get estimated sizes. Please not all measurements must be in a unit of inches.

Snug Underbust
Standing Bust
Leaning Bust
Lying Bust
Invisibra Size {{value}}
UK Size {{value}}


Invisibra Size {{value}}

Please note that our sizing suggestion is advisory only. You should judge the appropriateness of size when you receive the product.

Busting those bra sizing myths

If you’re surprised, or maybe shocked, by the result you got from the bra size calculator, that’s totally normal! Because most women underestimate their bra cup size. Maybe you’re looking at the result and thinking, there’s no way I’m a D/E/F cup. This may be a result of one of the biggest bra sizing myths people believe in, which is that a certain cup size means something. For example, women think B or C is average, D is bigger than average and anything above is D is ginormous. But bra sizing isn’t just about cup sizes. You have to look at the band size too. When you look at your band size as well as your cup size, you have a clearer picture of your boob size. Delve deeper into bra sizing and you’ll never look at bra sizes the same again.

What does your bra size mean for InvisiBra?

InvisiBra is a backless bra, so our sizing is different to normal bras that have back panels. Once you have your bra size, you can convert it to InvisiBra size. Don’t be tempted to just get the cup size you are, because your band size does affect the InvisiBra size you need. If you think about it, a 30C is really different from a 38C.

A backless bra doesn’t have bra straps and a back panel, all you have is the two stick on bra cups which you stick onto your boobs. So sizing for a backless bra is actually pretty flexible. The only real no-no is wearing a cup size that’s too big. Because cups that are too big will swamp your boobs and won’t give you the shape and support you’re looking for.

measure bra size to find your true bra size
measure bra size for invisibra

Why you should consider going for a smaller size

You probably want to avoid going too small if you’re wearing something tight fitting because of the possibility of a quad boob. But otherwise, you have the option to go for size smaller. There are two reasons why you might want this. Firstly, the smaller the stick on bra cup, the lighter it is, so it will give you more lift. Secondly, if you’re going for a fuller boob look (aka cleavage), then a smaller size will give you more of that. That’s because when you position the stick on bra cups, there’s a greater distance between small cups, meaning that the cups travel further together when you clip them together.

D/E/F/G cup ladies, InvisiBra can work for you

As long as you would describe your boobs as firm. If you’ve lost a lot of weight or gone through multiple pregnancies, and your boobs have lost a lot of elasticity, then InvisiBra will not give you much lift.

For G cup, your band size needs to be no more than 30 inches. For F cup, it should be no more than 32 inches. For EE cup, it should be no more than 34 inches. For DD cup, it should be no more than 36 inches. We recommend that you go for one of the lifting backless bras to get the maximum lift and support our bras offer.



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