How to Find Your Bra Size

Finding your bra size is easy - and important!

Pink bra hanging from clothes line
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Finding your bra size is so important to feel supported, comfortable, and confident in your undergarments. A well fitting bra not only looks better, it also feels better. If you've been suffering from digging bra straps, pinching underwires, or bra cup spillage, chances are your bra size needs an update. 

There are several different methods to measure and calculate your bra size. 

Option 1: Get Sized by a Bra Fitter 

Personally, I have fit thousands of women for bras!

It's been my extreme pleasure to help women try on and find bras in the sizes and styles that fit them best. Many bra fitters have undergone training and have day to day experience with the brands and bra styles they sell. Working with a bra fitter can be an efficient and enjoyable way to shop for bras. She can troubleshoot and fix fitting issues right on the spot, and ensure your bra is adjusted and fits well. I highly suggest working with a respected bra fitter if you can!

Option 2: Bra Calculator

Another option is by taking your underbust and bust measurements and inserting them into a bra calculator. Bra calculators use a pre-determined algorithm, or mathematical equation, to suggest a bra size. While calculators can be a helpful bra fitting tool, they can also lead to painful inaccuracies. If you pop your measurements into several calculators, you will get several contradicting bra size suggestions. Furthermore, a bra calculator does not have a human element. That means there's no person, you or a professional, taking things into account like bust shape, age, health issues, or personal comfort.

I suggest using a bra calculator only for a second opinion or to estimate a basic starting point before some trial and error while bra shopping. 

Option 3: At-home Self Measurement

Another option is to take your own measurements and use do some simple math to estimate your bra size. It doesn't require a calculator or a trip to a bra shop, and can be done on your own or with the help of a friend.

 Even if you think all your bras fit fine, take your measurements anyway. You might find out you're not the size you thought you were. You'll also be one step closer to experiencing the comfort and support of wearing a better-fitting bra.

What you'll need:

·A soft tape measure 

·If you don't have a tape measure: substitute a long piece of ribbon, string or twine. Keep a pair of scissors nearby to cut off the excess ribbon after measuring your body, as well as a flat yardstick to measure the ribbon.

·Your best fitting, non padded bra. It's OK if it doesn't fit perfectly. Measuring while wearing a bra is often easier and more accurate than wearing no bra at all.

·A paper and pen


Step 1: Find Your Band Size

The bra band provides almost all of your bra's support. A firm, well fitting bra band is key to a good fit. And because bra cup size is relative to your band size, it's important to get this right before moving on. Note: some people suggest to take measurements while bending over or laying down. These instructions work best while you are standing straight and tall.

1.     Loop the tape measure around your torso from just under your bust, behind you and below the shoulder blades, at your bra's band level, and back to under your bust.

2.     The tape measure should gently hug your body, staying parallel with the floor. Breathe naturally.

3.     Record your measurement in inches, rounding up to the nearest whole number.

4.     Depending on the brand of bra you'll be wearing, level of comfort, and support required, you will add 0-5 inches to this measurement. 

5.     If the measurement is odd, add 1, 3, or 5 inches (details below)

6.     If the measurement is even, add 0, 2, or 4 inches (details below)

Example: Your underbust or band measurement is 30 inches. This is an even number, so we'll add 0 and 2 to find our band starting sizes. Adding zero inches means your band size will be a 30. Adding two inches means your band size will be 32. 

If your underbust was 29 inches, you would add 1 and 3 inches to this measurement. The suggested band sizes would be 30 and 32 again. 

Remember, these are suggestions and every bra band will fit differently. In fact, some classically designed brands use an older method of bra measurements and you may want to add 4 or 5 inches. That means this same woman may wear a 34 band in certain lingerie brands. You can start with the middle number and use trial and error to determine the best fit for each bra. 

Step 2: Find Your Bust Measurement

Did you know that your cup size is based on your band size? That means as your band size changes, so does the cup size. It's important to start off with a well fitting band size before determining your cup size. 

1.     Using the tape measure again, measure around the fullest part of your chest, at nipple level. The tape measure should be gently hugging your body from your bust, around your back, and to your bust again. 

2.     Make sure the tape measure is parallel to the floor.

3.     Record this number in inches, rounding to the nearest whole number. 

4.     Using this number, you'll do some simple math to determine your cup size.

Example: Your bust measures 36". 

Step 3: Calculate Your Cup Size

Let's do some simple math to determine your suggested cup size. 

1.     Subtract your lowest band size (step 1) from your bust measurement (step 2). 

2.     Record this number.

3.     Using the chart below, determine your cup size for that band size based on this number. 

·0, your cup size is AA.

·1, your cup size is A.

·2, your cup size is B.

·3, your cup size is C.

·4, your cup size is D.

·5, your cup size is DD *or in some brands, an E cup. 

·6, your cup size is DDD *or in some brands, an F cup.

·7, your cup size is DDD *or in some brands, a G cup.

·8, your cup size is H


Example: If your bust measures 36", and your smallest band size is a 30, the difference is 6. That means, in a 30 band, your suggested cup size would be an F or DDD cup, depending on the manufacturer. 

Now you can use this as a starting point size when trying on bras. Keep in mind that every bra fits differently, and the calculations here will give you a basic starting point. In fact, in one shopping trip, you may find bras in different sizes or styles each fit well. I suggest trying bras in your alternate sizes. These are often referred to as "sister sizes". For instance, if you just measured yourself for a 30DDD or F, you can also try a 32DD or E, or a 34D. Find out more about what your bra size means and how the cup changes as the band size changes.

Be careful not to size too far up in the band just to achieve a smaller cup size. This practice may lead to a bra band that is too loose. A loose band will not support your bust. A firm, snug band will keep your bust lifted and stay in place. A good fit is essential for support. Not sure if your band fits? You can check out these 6 ways to tell if your bra fits - because that's even more important than knowing your size.

Use the steps above to find a starting point for your bra size and have fun. Have more questions? Ask me