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Measurement Guide

Measure With an Existing Ring

If you already own a ring that fits perfectly, measuring its diameter is the fastest and most accurate way to find your size.

The Diameter Method

  1. Find a ring that fits the exact finger you want to measure.
  2. Place a ruler flat on a table and place the ring on top of the ruler.
  3. Measure the straight distance straight across the center of the ring.
  4. Critical: Measure the INSIDE edge of the ring. Do not include the metal of the band in your measurement.
  5. Record the millimeter measurement, and enter it into our Ring Size Calculator to get your exact US size.

Written by Evelyn Moore

Evelyn is a certified GIA Gemologist with over a decade of experience in fine jewelry sizing and design. She ensures all conversion charts and measuring advice strictly adhere to ISO 8653 standards.