Sports Bra Calculator
Sports bra sizing starts from the same two measurements as everyday sizing, but the right garment depends on your impact level: a size that works for yoga will not control a run. Enter your measurements, pick your activity level, and get both the size and the support style to look for.
During exercise, breasts move in a figure-eight pattern, not just up and down, and unmanaged movement strains the skin's supportive ligaments regardless of size. The right style matters as much as the right number.
This calculation runs entirely in your browser. Your measurements are never stored or sent anywhere.
Compression, encapsulation, or both
Compression styles press tissue against the chest as one unit; they are simple, comfortable and effective for smaller volumes and lower impact. Encapsulation styles support each side in its own shaped cup, controlling the figure-eight motion far better, which makes them the serious choice above roughly a C cup or for running. Combination styles do both and dominate the high-impact shelf for good reason.
Fit checks specific to sport: the band must be firmer than your everyday band since it carries more load, straps should be wide or crossed, and a quick jump test in the fitting room tells the truth in three seconds. Bounce that you can feel is bounce the ligaments feel too.
When your sports size differs from your everyday size
Many people wear their measured size in encapsulation sports bras but go one band size down in stretchy compression styles, because the power fabric relaxes with wear and sweat. If a compression bra feels merely comfortable when brand new and dry, it will under-support by month two. Snug to the point of firm on day one is correct.
Frequently asked questions
Last updated August 2026.