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How To Measure Your Bra Size

How to measure your bra size BOOMBA

80% of women wear the wrong bra size. Yes, that’s right. That sure is a lot of women wearing the wrong bra! There is obviously a lot of confusion out there about how to measure your bra size. Not only is wearing the wrong size uncomfortable, but it also leads to bad posture and an overall unflattering shape.

Don’t worry. In this article, we’ll show you how to find the perfect fit so you can show off those beautiful curves.

What You Need

To find the right bra size, we’re going to need 3 things.

  1. Tape measure
  2. The best-fitting non-padded wired Bra
  3. Pen and paper to write down your measurements


Are you now all set? Let’s go!

How to Measure Your Bra Size

Step 1: Determine your band size.

Wrap the tape measure around your rib cage, positioning it under your bust. Make sure the measuring tape is snug but not dig into the skin. Now that you have the measurement, round it to the nearest whole number. If the number is even, add 4 inches. If the number is odd, add 5. Example: If your band size is 31, which is an odd number, add 5. So your band size is 36.

Step 2: Measure Your Bust Size.

Wrap the tape measure from behind over to the fullest part of your breast and ensure that the tape is parallel to the floor. This measurement is usually across the nipple. Make sure that it rests comfortably around your breast and that it’s not too tight or loose.

Step 3: Find your cup size.

Okay, we’ll need a bit of calculation in this part. But no worries! We still got you covered. Bust size minus band size equals your cup size. As simple as that. For example, if your bust size is 38 inches and your band size is 36 inches, then 38-36=2. Based on the chart below, you are a B cup.

Note that this chart uses US cup sizes.

Your BRA SIZE is your band size plus your cup size. Example: 36B

How to Choose the Right Ultra Boost Size

Now that you have measured your bra size, please take a look at the table below to choose the correct size for your BOOMBA inserts. We recommend sizing up in your bikini to accommodate for the boobage (BOOMBA insert).

Please note that Demi Boost, Perfect Boost and Invisible lift are one size fits A to D while Ultra Boost Inserts come in different sizes.



28A 6A 60A 75A AA
30A 8A 65A 80A AA
32A 10A 70A 85A AA
34A 12A 75A 90A A
36A 14A 80A 95A B
38A 16A 85A 100A C
40A 18A 90A 105A D
28B 6B 60B 75B AA
30B 8B 65B 80B AA
32B 10B 70B 85B A
34B 12B 75B 90B B
36B 14B 80B 95B C
38B 16B 85B 100B D
40B 18B 90B 105B E
28C 6C 60C 75C AA
30C 8C 65C 80C A
32C 10C 70C 85C B
34C 12C 75C 90C C
36C 14C 80C 95C D
38C 16C 85C 100C E
40C 18C 90C 105C F


28D 6D 60D 75D A
30D 8D 65D 80D B
32D 10D 70D 85D C
34D 12D 75D 90D D
36D 14D 80D 95D E
38D 16D 85D 100D F
28DD/E 6DD 60E 75E B
30DD/E 8DD 65E 80E C
32DD/E 10DD 70E 85E D
34DD/E 12DD 75E 90E E
36DD/E 14DD 80E 95E F
28DDD/F 6E 60F 75F C
30DDD/F 8E 65F 80F D
32DDD/F 10E 70F 85F E
34DDD/F 12E 75F 90F F
28G 6G 60G 75G D
30G 8G 65G 80G E
32G 10G 70G 85G F

How to Know If You Have the Right Bra Size

Once you’ve figured out your correct bra size, how do you know that it’s right? There’s only one way to find out. Test it! Make sure you try on different bras from different brands, as sizes can differ between brands.


Here’s a bra checklist:

  • The straps should stay on your shoulders and not pinch or dig in your skin.
  • The band should be snug enough but not too tight.
  • The underwire should sit comfortably under your bust.
  • The area between the cups should be flat, and only one finger can slide underneath it. Otherwise, it’s too loose.
  • The cups should fully cover your bust with no spillage on the sides or over the top.


With this information on hand, you can then confidently shop for any of the BOOMBA products. If you are still unsure, please send us an email or DM us and we would be glad to help.

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