How is the width of frames calculated? JINS Customer Support August 31, 2018 22:32 Updated Follow Please see below: Small Medium Large Frame width 130 - 134 mm 135 - 139 mm 140 - 145 mm Related articles How can I check the size of my frame? Can you help me choose a frame? May I try your frames on at home before purchasing? What are the types of lenses you offer? What is "Alternative fit"? Comments 0 comments Article is closed for comments.