Ring Size Guide   How to measure your finger 1. Wrap a piece of string or paper strip around the base of your finger. 2. Mark the string or paper where it overlaps to form a complete circle. 3. Measure the length of the section of string where it overlaps around the finger. 4. Compare your measurement with this chart to determine your ring size.   UK USA mm H 4 46.5 I 4.5 47.8 J 5 49 K 5 ½ 50.3 L 5 ¾ 51 L ½ 6 51.5 M 6 ¼ 52 M ½ 6 ½ 52.8 N 6 ¾ 53.8 N ½ 7 54 O 7 ¼ 55 O ½ 7 ½ 55.3 P 7 ¾ 56 P ½ 8 56.6 Q 8 ¼ 57 Q ½ 8 ½ 57.8 R 8 ¾ 58.8 R ½ 9 59.1 S 9 ¼ 60 S ½ 9 ½ 60.3 T 9 ¾ 61 T ½ 10 61.6 U 10 ¼ 62 U ½ 10 ½ 62.8 V 10 ¾ 63.9 V ½ 11 64.1 W 11 ¼ 65 W ½ 11 ½ 65.3 X 11 ¾ 66 X ½ 12 66.6 Y 12 ¼ 67 Y ½ 12 ½ 67.9 Z 12 ¾ 68.3 Z ½ 13 69.1 Z+1 13 ¼ 70.3 Z+2 13 ¾ 71 Z+3 14 72 Z+4 14 ½ 73.3 Z+5 15 74.8 Z+6 15 ½ 75.6 Please note that this is only a guide and not to be taken as 100% accurate.