Find Your Bra Size
Getting the right size bra is crucial to lock in all the benefits. Grab a tape measure and an unlined bra to see how you measure up in Nike Bras. If you don’t have a tape measure, string and a ruler work too.

First, Measure Your Underbust
Measure around the bra’s bottom band, just under the breast. The tape measure should feel snug. Round up to the closest measurement. If you don’t have a measuring tape, use a string and a ruler. Follow the above instructions. Lay the string on a flat surface and measure with the ruler.

Second, Measure Your Cup
With the tape measure parallel to the floor, lay the tape across the fullest point of your breast. Measure from the center of your chest to where your breast tissue ends on one side (where an underwire should sit). Round up to the closest measurement.

Use the charts below to convert your regular bra size into Nike Sports Bra sizes.
Scroll horizontally to see more sizes on each chart.
XS – 4X

Alpha Size XS S M L XL 2XL 1X 2X 3X 4X
Band/Cup Size 30A - 30E 32A - 32B 32C - 32E 34A - 34C 34D - 34E 36A - 36C 36D - 36E 38A - 38C 38D - 38E 40A - 40C 40D - 40E 42A - 42C 42D - 42E 44A - 44C 44D - 44E 46A - 46C 46D - 46E 48A - 48C 48D - 59E 50A - 50C


XS (A-C) – 4X (F-G)

Alpha/Cup Size XS (A-C) XS (D-E) XS (F-G)
Band/Cup Size 30A - 30C 32A - 32B 30D - 30E 30F - 30G
Alpha/Cup Size S (A-C) S (C-E) S (F-G)
Band/Cup Size 34A - 34B 32C 32D - 32E 34C 32F - 32G
Alpha/Cup Size M (A-B) M (C-E) M (F-G)
Band/Cup Size 36A - 36B 36C 34D - 34E 34F - 34G
Alpha/Cup Size L (A-B) L (C-E) L (F-G)
Band/Cup Size 38A - 38B 38C 36D - 36E 36F - 36G
Alpha/Cup Size XL (A-B) XL (C-E) XL (F-G)
Band/Cup Size 40A - 40B 40C 38D - 38E 38F - 38G
Alpha/Cup Size 2XL (A-B) 2XL (C-E) 2XL (F-G)
Band/Cup Size 42A - 42B 42C 40D - 40E 40F - 40G
Alpha/Cup Size 1X (A-B) 1X (C-E) 1X (F-G)
Band/Cup Size 44A - 44B 44C 42D - 42E 42F - 42G
Alpha/Cup Size 2X (A-B) 2X (C-E) 2X (F-G)
Band/Cup Size 46A - 46B 46C 44D - 44E 44F - 44G
Alpha/Cup Size 3X (A-B) 3X (C-E) 3X (F-G)
Band/Cup Size 48A - 48B 48C 46D - 46E 46F - 46G
Alpha/Cup Size 4X (A-B) 4X (C-E) 4X (F-G)
Band/Cup Size 50A - 50B 50C 48D - 48E 48F - 48G


To get the best fit within our Alpha/Cup size range, find your usual size (XS–4X), then find your usual cup size (A–G). For example, if you typically wear a size Medium and are a C cup, the “M (C–E)” should be your perfect size.