Will the size be biased? Dave November 27, 2019 14:58 Updated Follow The size may have a difference less than 2mm due to the difference of angle and the measuring tool. Related articles Do you have spring hinges glasses? How do I make sure the frame size is right for me? Do the frames come in different sizes? What should I do if the frame doesn't fit me well? How to choose frames? Comments 0 comments Please sign in to leave a comment.