All our ring sizes are based on circumference in mm, measured along the inside of the ring. The easiest way to determine a ring's circumference is to measure the relevant finger with a piece of string or paper. Mark the point where the two ends meet and measure the length against a ruler to find the circumference. The diameter of the finger may easily be identified by dividing the measured circumference with 3,14.

You can also use a ring you already have by measuring the inside circumference and following the same procedure as described above.

Remember that the size of your fingers usually differ from your right to your left hand, so make sure you measure the correct finger.