How to Measure Your Ring Size at Home

Finding your correct ring size helps ensure a comfortable fit and prevents damage to delicate antique pieces. Below are simple, reliable methods you can use at home.

Method 1: Measure an Existing Ring

This is the most accurate at-home method if you already have a ring that fits the intended finger.

You’ll Need:

• A well-fitting ring
• A ruler with millimeter (mm) measurements

Steps:

1.      Place the ring flat on a table.

2.      Measure straight across the inside diameter of the ring (edge to edge at the widest point).

3.      Use a ring size chart to match the diameter (in mm) to the correct U.S. ring size.

Tip: Make sure you measure the inner edge—not the outer edge.

Method 2: String or Paper Method

Best if you do not have another ring to compare.

You’ll Need:

• A piece of string or a thin strip of paper
• A pen
• A ruler (mm)

Steps:

1.      Wrap the string or paper around the base of your finger.

2.      Mark where the ends overlap.

3.      Measure the length between the marks in millimeters.

4.      Compare the measurement to a ring size chart to find your size.

Tip: Do not pull the string too tight—your ring should slide over the knuckle comfortably.

Getting the Most Accurate Measurement

• Measure at the end of the day. Fingers swell slightly, so this gives the most realistic result.
• Measure the knuckle. If your knuckle is significantly larger, size up slightly.
• Take multiple measurements. Try 2 to 3 times for consistency.
• Consider band width.
• Thin bands fit true to size.
• Wide bands may feel tighter—size up ¼ to ½ size.

Professional Sizing

For the most accurate result, a jeweler can measure your finger using a metal sizing set. If you're purchasing a delicate antique ring, this is the ideal method.

Ring Size Quick Reference (US Sizing)

Inside Diameter (mm)      US Size   

12.37 mm                        1

12.78 mm                        1.5

13.21 mm                        2

13.61 mm                        2.5

14.05 mm                        3

14.45 mm                        3.5

14.86 mm                        4

15.27 mm                        4.5

15.70 mm                        5       

16.10 mm                        5.5

16.51 mm                        6

16.92 mm                        6.5

17.32 mm                        7

17.73 mm                        7.5

18.14 mm                        8

18.54mm                        8.5

18.95 mm                        9

19.35 mm                        9.5

19.76 mm                        10     

20.17 mm                        10.5

20.57 mm                        11

20.98 mm                        11.5

21.39 mm                        12

21.79 mm                        12.5

22.20 mm                        13