Necklace

 Inches Centimeters
12 30
14 36
16 41
18 46
20 51
22 56
26 66
 

Ring

Sizing Sizing  Inside Diameter Inside Circumference
US/CA
UK
MM MM
4 H 15 47
5 J 16 49
6 L 16.5 52
7 N 17 54
8 P 18 57
9 R 19 60
10 T 20 62
11 V 20.5 65
12 X 21 67
13 Z 22 68

Bracelet | Bangle | Cuff

 Sizes Inches Centimeters
Extra Small 6 15
Small 6.5 17
Medium 7 18
Large 7.5 19

Anklet

 Sizes Inches Centimeters
Small 7-8 18-21
Medium 8-9 20-23
Large 9-20 23-26