Ring Size Converter

Free online ring size converter. Convert between US, UK, EU, Japan, China, and India ring sizes. Visual ring sizer, measurement guide, and printable ruler included.

Size Converter

System

Size

Visual Ring

— mm Diameter

— mm Circumference

Ring Width 4mm

Material

Measurement Guide

Wrap a string or strip of paper around the base of your finger

Mark where the string/paper overlaps with a pen

Measure the length in millimeters — this is your finger circumference

Enter the circumference below to find your ring size

Circumference (mm)

Size Chart

US	UK	EU	JP	CN	IN	Diameter (mm)	Circumference (mm)

Measurement Tips

Measure in the evening when your fingers are at their largest
Cold fingers can be up to half a size smaller
Wide rings (6mm+) may need half a size up
If your knuckle is larger than the finger base, measure both and choose a size in between

About Ring Size Converter

Convert ring sizes instantly between US, UK, EU/ISO, Japan, China, and India standards. Features a visual ring sizer with screen calibration, measurement guides, and a complete international size chart. Perfect for online jewelry shopping and gift buying.

Features

6 international ring size systems — US, UK, EU, Japan, China, India
Visual ring sizer with screen calibration for true-size display
String and paper strip measurement guides with step-by-step instructions
Complete size chart with diameter and circumference in millimeters
One-click copy for any size value
Material preview — see how your ring looks in Gold, Silver, Rose Gold, or Platinum