Ring Size Converter
Convert ring sizes between US, UK and EU systems or find your size from a ring's inside diameter or finger circumference in mm.
Tip: measure an existing ring's inside diameter with a ruler, or wrap a strip of paper around your finger and measure the length in mm (that's the EU/ISO size). Sizes are matched to the nearest standard size.
Need this done properly for your business?
Radiatus delivers secure cloud, DevOps & compliance engineering.
Privacy & Security
Runs entirely in your browser. No data is sent to any server.
How to Use
Pick what you know (US number, UK letter, EU circumference or diameter in mm) and enter the value to see all equivalent sizes.
Disclaimer: This tool is provided "as is" without warranty of any kind. Results are for educational and utility purposes.
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