As a woman, one of my consistent struggles is keeping track of my bra size.
It seems that by a certain age that a woman would know her own bra size, but your bra size can change depending on the brand and the various styles that the brand may make (such as strapless, balconette, etc.).
It is even advised to get your bra measurements taken once a year due to how styles, as well as your body, change.
Aging, hormone fluctuations, pregnancy, weight loss or gain, and stress are factors that can result in changes in your breasts.
When considering the various brands of lingerie and bras available, sizes may run differently. For instance, one brand’s DDD-cup may be smaller than the next brand’s DDD-cup.
Unless I decide to have my measurements taken every time I go bra shopping, I’m usually playing a guessing game on my size. How many can relate?
Learning how to efficiently calculate your bra size will be beneficial in the long run for a few reasons.
RELATED: Wearing The Right Size Bra Can Be Life Changing
The bra size calculator estimates your bra size according to your band (frame) and bust sizes:
You will need a measuring tape to measure around your torso directly under your bust, where the bra band would sit. Make sure the tape is level and snug.
For the most accurate measurements, measure to the nearest ¼ inch or ½ cm.
There are a few signs that indicate that you may not have found the right, let alone perfect, size bra.
RELATED: Most Women Wear The Wrong Size Bra – Are You One?
If all else fails with your ability to determine your true bra size, having a professional bra fitting is best.
Whether you’ve had a professional fitting many times or later in your life, you will be amazed by the results of being fitted with the perfect bra.
The professional fitters can assist you with any problems you have had with choosing the right size bra on your own, as well as introduce you to the best bras that work best for your shape and figure.
Go to your local lingerie boutique or specialty store to get your bra fitting so you can start bra shopping the proper way.
In the end, not only do you save yourself from an improper-looking outfit, but also from any back and breast pains that may come with consistently wearing an ill-fitted bra; this especially holds true for women with larger breasts.
A bra size calculator takes your underbust (band) and overbust (full bust) measurements—usually in inches—and determines your band size and cup size using formulas or sizing charts.
Once you have your band size:
Measure around the fullest part of your bust.
Subtract band size from bust measurement—the difference in inches gives your cup size:
1″ → A, 2″ → B, 3″ → C,
Step 1: Underbust (Band):
Wrap a soft tape around just under your breasts, keeping it level.
Round to the nearest even number → this is your band size.
Step 2: Overbust:
Measure around the fullest part of the bust with the tape measure.
Step 3: Cup Calculation:
Subtract band from bust. Use the difference-to-cup chart: 0″→AA, 1→A, 2→B, 3→C, etc.
Some U.S. methods add 4 inches to the underbust to simplify sizing (e.g., a 30″ underbust becomes band size 34). It’s used less now—many experts prefer rounding to the nearest even number without adding inches.
It means all measurements are taken in inches (not centimetres). Just measure in inches—no conversion needed!
In the U.S., bras use inch-based sizes and lettered cups (A, B, C, D, DD, etc.) Other countries may use centimeters or add different letters.
Most calculators:
Accept underbust + overbust measurements.
Apply rounding and formulas.
Use a lookup table to convert the difference into cup letters.
Provide final size (e.g., 34C)
Measure with a non-padded or lightly padded bra.
Keep tape snug but not tight.
Round to even numbers for band, nearest whole number for bust
Top tools come from:
Calculator.net – US, UK, EU sizes included
B.Tempt’d and SKIMS – interactive, guidance-based
Tools combining measurement guidance and country-specific sizing charts are most reliable.
Input:
Band size: even inch number (e.g., 34)
Bust size: full bust measurement (e.g., 37)
Calculator returns: Cup = C, so size = 34C
Cup size = Overbust (“bust”) − Band. Then match the inch difference:
By subscribing, you consent to receive emails from BlackDoctor.com. You may unsubscribe at any time. Privacy Policy & Terms of Service.
