Ring Size Converter
Convert ring sizes between US, UK, Europe, and Japan standard systems.
Ring Size Calculator
How to Measure
To find your diameter at home, measure the **inside width** of a ring that fits you comfortably. For circumference, wrap a strip of paper around your finger and measure the length.
System Guide
- US/Canada: Numerical scale (0-16).
- UK/AU: Alphabetical scale (A-Z).
- Europe/ISO: Based on circumference in mm.
Ring Size Converter & Diameter Chart
Convert ring sizes across US, UK, Europe, and Japan using diameter and circumference measurements.
Input Measure
Enter the inside diameter of a ring in millimeters.
Match Size
Find the equivalent size in US, UK (Alphabetical), or EU standards.
Frequently Asked Questions
Wrap a piece of string around your finger, mark it, and measure it in millimeters to get the circumference.
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