I'm definitely a "marge" in Coeur sizing and can go between medium or large depending on how I want the item to fit. I ordered a large in this tank, and it's the perfect fit for a run singlet. I like my running tops/tanks a little loose (like a Des Linden singlet look vs. a tight running top), and this tank is the perfect drape. It's light and doesn't feel heavy when it gets soaked with sweat (you can't see obvious sweat marks when it's wet either), and the color is so pretty too. The cut is great, and the simple stripe detail adds to the tank. So happy to have this in my run gear collection!