I am S in sports bras. 32 B or 34 A-B in Victorias secret (depending on model) and It fits ok (could be looser in front chest, sternum area). But I give only 3 stars, cause few sequins were already in the bag, some are very loose. Guys, I pay $20, so I don't want to sew it back on myself:/ (and I have to, cause no time to change or search for new one).