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
Paper (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’re between sizes, choose the larger size. Ring sizes are reasonably forgiving, but if your ring still feels slightly loose, every order includes a complimentary silicone ring size decreaser.

We'll also send you a free ring sizer, so you'll only need to measure with string on your first order.

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.