Range of Jack Sterling sterling silver signet rings stacked on a ring sizer mandrel

Ring Size Guide

Step 1

Get a piece of string (dental floss works well)

Hands holding a measured length of string between thumb and forefinger to check ring size, Jack Sterling sizing guide

Step 2

Wrap it tightly & mark where the string overlaps

Marking a piece of string wrapped around a finger with a marker pen to measure ring size, Jack Sterling sizing guide

Step 3

Measure the distance in millimetres.

Measuring a length of string against a ruler to determine ring size in millimetres, Jack Sterling ring sizing guide

Use the chart below to convert your measurement to ring size.

String (mm) 474849.550.5525354.555.55758.559.5616263.5656667.568.5707172.5
Ring Size (US) 44.555.566.577.588.599.51010.51111.51212.51313.514
String (mm) Ring Size (US)
47 4
48 4.5
49.5 5
50.5 5.5
52 6
53 6.5
54.5 7
55.5 7.5
57 8
58.5 8.5
59.5 9
61 9.5
62 10
63.5 10.5
65 11
66 11.5
67.5 12
68.5 12.5
70 13
71 13.5
72.5 14

A few things to keep in mind

If you'd prefer, we can send you a free ring sizer here. We include one of these with every ring order, so you'll only need to measure with string on your first order.

If you’re between sizes, choose the larger size. If your ring feels slightly loose, every order includes a complimentary silicone ring size decreaser.

We keep sizes 6, 7, 8, 9, 10, 11 and 12 ready to ship. For all other sizes, including half sizes, select “Custom Size” and allow an additional 5-10 days for production.

Buying for someone else? The most common men’s sizes are 9 and 10. The most common women’s sizes are 6 and 7.

If you select the wrong size, returns are straightforward. You can review our full Refund Policy.