Sure, sunglasses protect your eyes and help you see, but they can also lend an instant, undeniable cool factor to just about anyone. Said cool factor is most apparent when sunglasses fit well, balance your features, and look like they were made for your face. Because one-size-flatters-all shades are unfortunately not a thing, we asked Bobbi Brown, makeup artist, glasses expert, and author of the new book Bobbi Brown: Everything Eyes, for her top tips for finding flattering sunglasses for every face shape.

First Things First: Diagnose Your Face Shape
Finding the right sunglasses for your face shape is going to be difficult if you don't know what your shape is. According to Brown, your face is considered round if the width and length are roughly the same. (You don't need to bust out a ruler, just estimate this by measuring the span with your fingers.) You have a square face if your jawline is strong and your forehead is broad. An oval-shaped face is "long and thin, with a chin slightly narrower than your forehead," says Brown. And finally, a heart-shaped face is wider at the forehead but significantly narrower at the chin. If you're still unsure where you fall, ask someone: "Anyone working at a glasses store or makeup counter will be trained to tell you what your face shape is." Easy enough.

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