US and Canada Ring Size Guide

The United States and Canada use a numerical ring sizing system that ranges from approximately size 3 to 13.5 for women and 8 to 16 for men. This guide provides detailed information about the US/Canada sizing system, including measurement specifications and practical conversion information.

US/Canada Ring Size Chart

Complete Size Reference Table

US/Canada Size Inside Diameter (mm) Inside Diameter (inches) Inside Circumference (mm) Inside Circumference (inches)
3 14.1 0.55 44.2 1.74
3.5 14.5 0.57 45.5 1.79
4 14.9 0.58 46.8 1.84
4.5 15.3 0.60 48.0 1.89
5 15.7 0.62 49.3 1.94
5.5 16.1 0.63 50.6 1.99
6 16.5 0.65 51.9 2.04
6.5 16.9 0.67 53.1 2.09
7 17.3 0.68 54.4 2.14
7.5 17.7 0.70 55.7 2.19
8 18.1 0.71 57.0 2.24
8.5 18.5 0.73 58.3 2.29
9 18.9 0.75 59.5 2.34
9.5 19.4 0.76 60.8 2.39
US/Canada Size Inside Diameter (mm) Inside Diameter (inches) Inside Circumference (mm) Inside Circumference (inches)
10 19.8 0.78 62.1 2.44
10.5 20.2 0.79 63.4 2.49
11 20.6 0.81 64.6 2.54
11.5 21.0 0.83 65.9 2.59
12 21.4 0.84 67.2 2.64
12.5 21.8 0.86 68.5 2.69
13 22.2 0.87 69.7 2.74
13.5 22.6 0.89 71.0 2.79
14 23.0 0.91 72.3 2.84
14.5 23.4 0.92 73.6 2.89
15 23.8 0.94 74.8 2.94

Understanding US & Canada Ring Sizes

The American and Canadian ring sizing system is based on a numerical scale with whole and half sizes. The difference between consecutive sizes is approximately 0.4mm in diameter or 1.25mm in circumference. Here's what you need to know about this system:

Size Range Overview

  • Common Women's Sizes: Typically range from size 3 to 9, with the average being 6 to 6.5
  • Common Men's Sizes: Usually range from size 8 to 14, with the average being 9 to 10
  • Half Sizes: For a more precise fit, half sizes (e.g., 6.5, 7.5) are widely available
  • Quarter Sizes: Some specialty jewelers offer quarter sizes for an even more exact fit

How to Measure for US & Canada Ring Sizes

To determine your US or Canadian ring size, you can use several methods:

Measurement Methods

Using a Plastic Ring Sizer

Many jewelry stores offer plastic ring sizers that can be adjusted to fit your finger. These provide direct readings in US sizes.

Measuring Diameter

Measure the inside diameter of a ring that fits you well (in millimeters), then use the chart above to find your size.

Measuring Circumference

Wrap a piece of string or paper strip around your finger, mark where it overlaps, measure the length in millimeters, and use the chart to convert to your US size.

Professional Resources

View Detailed Measurement Guide