Measure the diameter

If you already have a ring that fits the finger you’d like to wear your new ring on, you can measure the internal diameter of the ring. Do this by placing your ring on top of a ruler and taking the measurement from the internal centre left hand side to the internal centre right hand side.

That measurement is called the internal diameter.

Take a look at the Diameter column in the table and find the closest match in mm to your measurement. Again, size up if you’re in between two sizes.