Measure the inside diameter of an existing ring using a ruler or caliper
Record the diameter in millimeters (mm)
Use a ring size chart to match the diameter to your size
Measure your finger circumference with a soft measuring tape
Record the circumference in millimeters (mm)
Use a ring size chart to match circumference to your size
If you don’t have a tape, wrap a strip of paper or string around your finger
Mark where it overlaps and measure the length in millimeters
Use a ring size chart to match the length to your size
Check ring fit by trying on a ring in the same size (if available)
Consider sizing adjustments for comfort (e.g., slightly larger for thick knuckles or colder temperatures)