Check out our 3 Fit Fundementals:

woman in bra highlighting bottom band
1. Check the bottom band

Make sure the bottom band is snug and lies flat across your back — not riding up or loose around your rib cage.

woman in bra with bra cups illustrated
2. Then check the cups

The cups should fit smoothly — spilling out the sides or front means the cup size is too small, while extra space means the cups are too big.

woman in bra highlighting straps
3. Last thing: the straps

Straps should lie smoothly against your skin, without sliding around or digging uncomfortably into your skin.

You can also shop for your sister size

Sister sizes are bra sizes that are not your true cup or band sizes, but they are equivalents. For example, the sister sizes of a 36D include 34DD and 38C. This makes shopping easier and can help you find the right bra that fits you best. Continue on to the size chart below to find your sister size.

photo of two women with numbers identifying the parts of the body needing to be measured to ensure a good bra fit
You’ll need a flexible tape measure. It’s also best to wear a bra that doesn’t change your shape — no padding or compression. You can also just skip the bra.
  1. Measure your rib cage
    Start your measurements by finding your band size. Measure around your rib cage where the bottom band would sit. The tape measure should feel quite snug. If you get a fraction, round down to the nearest inch. Using this chart, find your corresponding band size based on your measurement.
  2. Measure your bust
    Next, find your cup size. Measure around the fullest part of your boobs — which may not be the center — and round up to the nearest inch. Then subtract your rib cage measurement. The difference in inches is your suggested cup size. If you get a fraction, round up to the larger size.

Want help from an expert? Ask a guru.

Calculate your bra size:

Not sure of your measurements? Check out our how to measure section above.

Calculate your bra size:

Not sure of your measurements? Check out our how to measure section above.

Find your alpha size (XS-XXL):

A B C D
30 XS XS XS S
32 S S S M
34 M M M L
36 L L L XL
38 XL XL XL XXL
40 XXL XXL XXL

Find your alpha size (XS-XXL):

A B C D
30 XS XS XS S
32 S S S M
34 M M M L
36 L L L XL
38 XL XL XL XXL
40 XXL XXL XXL

Find your alpha size (XS-XXL):

A B C D
30 XS XS XS S
32 S S S M
34 M M M L
36 L L L XL
38 XL XL XL XXL
40 XXL XXL XXL

Find your alpha size (XS-XXL):

A B C D
30 XS XS XS S
32 S S S M
34 M M M L
36 L L L XL
38 XL XL XL XXL
40 XXL XXL XXL

Find your alpha size (XS-XXL):

A B C D
30 XS XS XS S
32 S S S M
34 M M M L
36 L L L XL
38 XL XL XL XXL
40 XXL XXL XXL

Find your alpha size (XS-XXL):

A B C D
30 XS XS XS S
32 S S S M
34 M M M L
36 L L L XL
38 XL XL XL XXL
40 XXL XXL XXL

Find your alpha size (XS-XXL):

A B C D
30 XS XS XS S
32 S S S M
34 M M M L
36 L L L XL
38 XL XL XL XXL
40 XXL XXL XXL