STEP 1: Cut a piece of thread and wrap it around your finger.

STEP 2: Simply put a mark or cut where the thread crosses each other

STEP 3 : Measure the length of the thread in MM.

 

RING SIZE (INDIAN) CIRCUMFERENCE (in MM)
1 41.01
2 42.7
3 42.9
4 43.6
5 44.8
6 46.1
7 47.4
8 48
9 48.7
10 50
11 51.2
12 51.9
13 53.1
14 54.4
15 55.1
16 56.3
17 57
18 58.3
19 58.9
20 60.2
21 60.8
22 62.1
23 62.7
24 64
25 63.6
26 65.9