Find Your Bra Size




About: Learn more about me here: or follow me on Twitter (@shesparticular) (if you're into that sort of thing).

It's important to make sure that your bra fits well - an ill-fitting one isn't just uncomfortable, it can lead to back and shoulder pain, poor posture, and it tends to look bad as well.

Finding your bra size isn't hard - it just requires a measuring tape and a little simple math.

Note: There are (kind of goofy) illustrations of boobs in the following steps; if they offend you, I'm sorry in advance. If it offends you that they're just drawings (and not real boobs), sorry about that too.

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Step 1: Measuring the Band Size

To determine the band size you need, measure around your chest just under your bust (just under the breasts). Make sure that the tape is against your body and straight across your back. Exhale as you take the measurement, but try not to pull the tape too tight (it should not dig into your skin at all).

Round all fractional measurements to the nearest whole number. If the number you get is even, add 4 inches; if it's odd, add 5 inches - jot that number down, it's your band size (the 34 portion of 34D, etc.)

When measuring, it may help to have someone else measure you to ensure that the tape is not twisted, and that it's parallel to the floor around the back.

Step 2: Measuring the Cup Size

Place the measuring tape across the fullest portion of your bust, ensuring that it is parallel to the floor, and not digging in or gaping away from your body. If needed (depending on the size and shape of your breasts), this measurement can be taken while wearing a non-padded bra - just make sure that it is not too tight or binding.

Round all fractional measurements to the nearest whole number.

From this number, subtract the number for the band size - this will tell you your cup size (see chart in next step).

Step 3: Getting a Better Bra

This chart will help to determine what bra size you need.

A few things to remember:
1. The center portion of a bra should fit between the breasts and should sit against the skin, not gap outwards.
2. Straps should not dig into the shoulders or hurt. If they do, try loosening them slightly, or try adjusting the band of your bra to make it looser.
3. The back band of the bra should sit across your back below the shoulder blades. If it pulls upwards, try loosening the shoulder straps.
4. If your bra has underwire, they should not dig in to your body or feel uncomfortable or painful - this is a sign that the bra does not fit you well.
5. The fabric of the cup portion should not bunch up (it's too big) or not cover the breast (too small).
6. If you gain or lose a lot of weight, you should re-measure and consider getting new bras as ill-fitting ones are rather uncomfortable.

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    52 Discussions


    3 years ago

    This doesn't work for me either... According to this, I'm an A. But A cups are too small for me. In cheap bras, a B fits well; in an expensive bra, a C fits well.


    3 years ago

    Ok so I add 5 inches to get my band size.

    Then deduct my breast size from that.

    I get negative 1.

    So I must be indented then lol.

    This is nonsense sorry.

    I have plenty of boobage and wear a comfortable C for years now.


    3 years ago

    Measure loosely around the fullest part of your bust, with the tape straight across and around your back, bringing it to the front.


    6 years ago

    I'm sorry my sweet, but adding inches only works for extremely bony women or obese women who slip them on, over their heads.

    1 reply

    6 years ago on Introduction

    this method was inaccurate for myself and i noticed it was for other readers ...but it got me thinking, every body is different so here's another measurement technique i some methods don't work for everyone so try a different one. :)

    Holy I have a Big bra size !!!! Im 13 and I have a DDD !!!!!! Never thought that > :(


    8 years ago on Step 3

    this doesnt make any sense to me. why add 4 or 5 inches? i did that and my bust is 40 and band is 39, that means im a b cup which i am not. they way i measure bra sizes is around the bust, 40 and around the band, 36ish, tht number difference is how i calculate not by adding numbers, the difference is about 4inches and that puts me at a d which i am. not a b.

    1 reply

    8 years ago on Step 3

    The shape of your breast plate is also a factor, flat breast plates can affect the over-bust measurements , while the cup sizes stay the same. To avoid this, Try and be very vigilant about keeping the measuring tape flush with your skin.

    Ultimately, you only know what bra size you are when you try on a bra and it lines up and fits perfectly. But this is a great system to know which end of the clothing rack you should start looking.


    8 years ago on Step 3

    The problem with this is that it doesn't actually work. The vast majority of women aren't wearing the right size bra, and the only way you're going to get the correct size by measuring the bust portion is if the bra you're wearing supports you properly without the underwire popping out from under the bust, poking out from the middle of your chest, or digging into your ribs on the side. If any of those are true, you're very likely wearing too large a band size and far, far too small a cup size. In other words, you can only find your exact bra size with a measuring tape if you're already wearing the right size!

    Also, your bra sizes stop halfway up the scale - it's possible to buy bras off the rack that go to J cup. It has nothing to do with being fat, and everything to do with how much breast material is present.

    According to the above measurements, which I always followed, I'm a 40DD, because DD was as high as my cup projection ever allowed, and I suffered through 20 or so years of discomfort and pain as a result. 5 years ago I was hired on at a lingerie shop, and I was immediately fitted by the owner as a 38I.

    40DD and 38I are not near each other, but the former is what I got from a measuring tape, and the latter is what I got from an experienced fitter who didn't touch a tape. :D

    I have since lost about 45lbs, and I am down to a 36H, which is another matter... women think they're losing cup size when they lose weight, when most of the sagging, bagging, and unhappiness comes from swimming around in a HUGE band size. Your band SHOULD be tight - it's where your support comes from. Bra straps are for shaping - if you have to tighten them to get lift, you need a tighter band and a larger cup, probably.

    Anywho, just thought I would mention that. Sizes over F are really common - stopping at triple-D is like not showing women's shoe sizes over an 8.

    Good luck and thank you for the info either way, its good to see people who want to inform others!! :)

    3 replies

    Thanks for your comments!

    I'm afraid I'm not sure what you mean "doesn't work" or why you would need to be wearing the right size bra to fit yourself using a measuring tape. As noted here, you should measure while not wearing a bra (unless the shape of your breasts would make that difficult - in which case they could be supported with your hands while someone helps you measure, or with a bra that lifts them and is as well-fitted as possible). Step 3 here also provides some additional information about signs that a bra doesn't fit well (straps digging in, the center gaping away from the chest, etc.).

    Regarding larger sizes, I am personally well aware of the scale for sizing going larger than indicated here (before I had surgery I was a 34FFF). I only made the chart/list go as far as DDD because I could not fit more information on it. I should have indicate that the "pattern" of sizing follows the same way - adding one inch to the difference between the measurements means adding a letter size.

    As noted in the tips in step 3, gaining or losing weight is for sure a reason to re-measure yourself. That said, the band of your bra should be snug and it should fit against your skin well/comfortably, but should not be "tight" - it should not dig into the skin or feel like it is digging in. Also, it should not pull up across your back, if it does, the shoulder straps of the bra are likely too tight and the band may be too large.

    Thanks again for all your comments!

    Thank you from a guy Shesparticular. The next time my wife goes shopping for a new bra, at least I will know something that might help.


    10 years ago on Introduction

    The worst part about censorship is ****** *** *******.

    Good Ible. I just did the math, and mine is a "AAAAA" by those standards. The measurements are the same. This of course is not surprising, as I'm male.

    4 replies

    Reply 8 years ago on Introduction

    Censored... I wonder what is so special about a woman's nipples that they must be censored, or it is indecent to breast feed in public....

    That also reminds me of an old joke: How do you make 2 lbs of fat look beautiful? Put a nipple on it. :D


    Reply 10 years ago on Introduction

    . . .and now I'm dying to know what it would say. Thanks - I guess I should have mentioned it's not exactly an 'ible for the fellas, but I guess it's a good thing to know how to do just the same.


    Reply 10 years ago on Introduction

    I was SORELY SORELY tempted to post pictures...but I can't find my camera. Literally, its gone. I'm quite shaken.