Bras and tops can sometimes feel like intimidating enemies, rather than welcoming allies. When garments fit poorly they can pinch and sag in key areas. Bra straps commonly fall off shoulders throughout the day or leave marks on sensitive skin by sundown. Transform your relationship with all of the clothes on your upper half, especially bras, with just a couple of measurements. Taking your bust measurement in inches conveniently translates directly to the bra-sizing charts in the United States and can also be applied to sewing patterns.

Step 1

Wrap the measuring tape around your torso horizontally, keeping the end of the measuring tape at the front of your body. Place the tape directly below your armpits and directly above your breasts, generally where your bra strap would meet the cup of your bra on your body.

Step 2

Hold the measuring tape gently around your body and take note of the circumference of this area, for example 34 inches or 38 inches. This measurement is your bra band size. If you measure an odd number, round the number up to the next even number. For example, if you measure 35 inches, your band size would be 36 inches. This is the number you see on the tag when you buy a bra.

Step 3

Wrap the measuring tape around the widest area of your bust, making sure the measuring tape remains parallel with the ground. Hold the tape gently around the bust so you are not squeezing your breasts.

Step 4

Make a note of this measurement -- for example, 36 inches or 40 inches. This measurement is your cup size.

Step 5

Subtract the bra band measurement from your cup-size measurement. Make a note of the difference between the two measurements. For example, if you have a cup size of 36 inches and a band size of 34 inches, the difference is 2 inches.

Step 6

Apply this difference to a sizing chart to get your final cup size. A difference of 1 inch is a cup size A, while 2 inches is a cup size B. A 3-inch difference represents a cup size of C and so on. The bigger the difference is, the larger your cup size will be. This letter pairs with the bra band number to get your final bra size, for example, 36B.

Step 7

Save the original band and cup measurements in inches for any number of sewing or alteration projects as well. Measure your bust size every once in a while to make sure your measurements remain accurate for shopping and alterations.