How to size your finger with a piece of string:
1. First, cut a thin paper or thread and wrap it around your finger.
Ensure the thread is below the joint and close to the knuckle.
2. Mark the location where the thread meets and measure the distance.
To be most accurate, use millimeters rather than inches.
3. Measure your finger a few times to ensure the sizing is correct.
4. Use the Chart A below to determine your ring size.
How to size your finger using a ring that fits you already:
1. Locate the ring that already fits you comfortable on your chosen finger.
2. Use a ruler and measure the diameter across in millimeters.
3. Use the Chart B below to determine your ring size.