: The card edge aligns exactly with the outer corner of your eye.
: The card edge ends before reaching the outer corner of your eye. Understanding Sunglasses Measurements buy sunglasses by size
Most sunglasses list three key numbers in millimeters (e.g., 52-18-140) on the inside of the temple arm: Sunglasses and Eyeglasses Size Guide - Mia Burton : The card edge aligns exactly with the
: Stand in front of a mirror and place the short edge of the card against the center of your nose. To buy sunglasses by size, you can use
To buy sunglasses by size, you can use a common household item like a credit card (or any standard-sized paper card) as a quick reference tool. Because a standard card is roughly the width of a "Standard" lens (54mm), it acts as a reliable benchmark for finding your frame category.