Wrap a thin strip of paper or string snugly around the base of your finger
Mark where the ends meet
Measure the length with a ruler in millimeters
Compare the measurement to a ring size chart
Repeat the measurement 2 to 3 times for accuracy
Measure at the end of the day when fingers are slightly larger
Measure the exact finger and hand you plan to wear the ring on
Make sure the paper or string is snug but not tight
If your knuckle is larger, measure both the knuckle and the base of the finger
Choose a size that can slide over the knuckle comfortably
Use a ring you already own by measuring its inner diameter
Match the inner diameter to a ring size chart
Check your size in warm and cool conditions if your fingers change size often
If you are between sizes, choose the larger size