Will the size be biased? Alvin November 20, 2019 07:51 Updated Follow The size may have a difference less than 2mm due to the difference of angle and the measuring tool. Related articles How do I make sure the frame size is right for me? How To Measure Your Frame Size? How to Adjust Your Eyeglasses? Frame Size and Strong Rx What're the difference between Tint lens, Photochromic lens and Polarized lens? Comments 0 comments Please sign in to leave a comment.