How to Figure Out Your Bra Size

For most women, bra shopping is a chore. Running through the department store and buying the same style and size isn’t the best solution to finding a bra that fits. But finding the right size bra can be a life-changing event. Not only is a well-fitting bra more supportive and comfortable, it also provides a solid foundation underneath your clothes so that you can easily transform your appearance, helping you look and feel put-together.

To help you take the guesswork out of finding your size, The Budget Fashionista is here to shed some light on this mysterious system. All you need to do is follow these three easy steps. You’ll just need a flexible tape measure and your best-fitting unpadded bra.

How to Measure for Bra Size

Determine your band size.

Begin by standing straight with your arms at your sides and take a snug, smooth measurement around your back, underneath your armpits, and just under your bust with the tape measure. If the measurement is even, add 4 inches. If the measurement is odd, add 5 inches to get your band size. So if you measure 29 inches around, your band size is a 34.
TIP: If you’re a full-figured women and measure 36 inches or higher, you’ll need to add 2 inches if it’s an even number; add 3 inches if it’s an odd number.

Find your bust size.

Next, while still standing straight with your arms at your sides, measure around your back, underneath your armpits at the fullest part of your bust. Again, be sure you’re pulling the tape measure until it’s taut but not pinching or digging into your bust.
TIP: If this measurement fall in between whole numbers, round up to the nearest whole inch. So, for example, if you measure 361/2, your bust size is a 37.

Calculate your cup size.

Finally subtract your bust size (step 2) from your band size (step 1). The difference will give you your cup size. Remember, each inch of difference is equal to one full cup size. In this case, the correct bra size would be a C cup.

You can look up your cup size here:
if the difference is then your cup size is
less than 1 inches AA
1 inches A
2 inches B
3 inches C
4 inches D
5 inches DD or E
6 inches DDD or F
7 inches G

The Bra Fitting Tips & Rules

Our bodies change for all sorts of reasons over the course of our lives (age, weight variations, pregnancy, and use of the contraceptive pill). So, if you want to look and feel as good as you deserve to, follow these rules.

Do . . .

  • Get measured for a bra at least twice per year by a professional bra fitter
  • Wash your bras in lukewarm water, using a gentle soap like baby detergent, Ivory Snow, or even baby shampoo
  • Never, ever, ever place your bras in the dryer
  • Wait at least 1 week after your period before trying and purchasing new bras
  • Always try on bras before purchasing them—you will not wear the same-sized bra in every bra
  • Rotate your bras every day to extend the life of the bra
  • Focus on fit rather than fashion when looking for everyday bras

Don’t . . .

  • Visible panty-line (I see London, I see France…)
  • Form-fitting top with heavily detailed bra (you can see bra imprint through top)
  • Tube top with no bra (and you need one)

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    Catherine Brock

    As a Southern California transplant now living in the Midwest, Catherine has turned layering into an art form and accepted that UGGs actually do have a place in the stylish lady's wardrobe. She's been featured in Woman's World Magazine,, Refinery29, and has made appearances on ABC7 Chicago, FOX2News St. Louis, KCAL9 Los Angeles, Fox19 Cincinnati, WGN TV Chicago and WCPO TV Cincinnati.

    Blog Comments

    I disagree with this style of measuring because it gives me the wrong size. According to the under the bust style, I am a 34B. However, a B cup is too small for me. I prefer the under the armpit measurement, which gives me a 32C, which fits perfectly.

    Mary, 32C and 34B are sister sizes…essentially, both sizes will fit the same measurements, although one might fit better or worse depending on the unique body shape of an individual. This way of measuring isn’t perfect, but it gives you a start-off point, and after that you can move up or down a sister size until you find the perfect fit.

    Should one be wearing a bra or not for finding the correct size?

    This way of measuring is absolutely incorrect. Bra sizes were measured this way befor bra bands incorporated elastic, therefor making this method out dated. The correct way, that will give you a decent shape and an even semi supportive bra is to take your underbust measurement as your band (odd numbers may go up or down, while down usually fits better; however 27 and under don’t have that option) and then calculate your cups size. I measure 27 under and 34-35 over and wear a 28 E/F UK. it fits MUCH better than the 32 c I measure at Victoria’s Secret and cant fit half my breast into and better even than the 32 DD that I bought from Victoria’s Secret an still spilt out of. Anyone having issues and thinking bras are just uncomfortable should try tho method and visit And Invest in your chest’s blog is helpful for problems too

    The difference between my two measurements is 11 inches. What cup is that? I wear a 40 K cup I know I should wear a 38, but there is a little more room in the 40 cup but it is not quite big enough. I do have the problem of falling out the bottom of the bra as there is a gap at the front where it does not touch me at all.

    For some reason, this measuring system gave me a 36AA, because I got -1 when I subtracted, however my bra size is a 34B. Which, I think fits WAY nicer. This measuring system is way off.

    Don’t add any inches to your underbust measurement. As a guess, I’d say your measurements are probably about 31 under and 35 over? That would put you in either a 30D or 32C, which are sister sizes of 34B, but you should try them out!

    I’m apparently a 36B..? Please. I can’t even fit a C cup bra.

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