Ring Size Converter

Convert international ring sizes using standard charts.

Sizes are approximate. Conversions matched by closest diameter.

Ring Size Converter: US, UK, EU, Japan

Find your perfect fit. Convert ring sizes between US, UK, Europe, Japan, and diameter measurements (mm).

Perfect Fit Guide

Ring sizes are measured by the inside diameter of the ring. Common standards include US (numerical), UK (alphabetical), and EU (circumference or diameter).

Sizing Tips

  • Measure your finger at the end of the day when it is largest.
  • The ring should slide over the knuckle but not fall off.
  • If you fall between two sizes, choose the larger one.

Frequently Asked Questions