It can be difficult to tell if your sunglasses will be comfortable if you don’t have a chance to try them on in person. If you have a favorite pair of glasses already, you can start by checking their measurements, though as we noted above, this isn’t a guarantee that another pair with the same measurements will have the same fit. A visit to your eye doctor will also provide accurate frame and lens measurements. “Your sunglasses should sit comfortably on your face without creating pressure on either side of the head,” says Layman. He recommends that your glasses sit in the middle of your face, “no higher than your eyebrows,” and match the width of your face at the temples without digging in. The arms should fit securely and comfortably around your ears and not slip out of place when you move your head.