There are several ways to easily find your ring size at home.
The most accurate way is to use a ring sizing gauge.

Another option is to print off the chart below and use a ring that currently fits you well to determine your size. 
Printable PDF Ring Sizing Tool
You can also measure your finger by following these simple steps:
1. Wrap a strip of paper around your finger and mark where the paper meets itself.
2. Straighten the paper out and measure the strip against a ruler. This is the circumference of your finger.
3. Compare your measurement against the following conversion chart to find your size:
|  | Millimeters | Inches | ||
| US Ring Size | Diameter | Circumference | Diameter | Circumference | 
| 4 | 14.9 | 46.8 | 0.586 | 1.84 | 
| 4.5 | 15.3 | 48.0 | 0.602 | 1.89 | 
| 5 | 15.7 | 49.3 | 0.618 | 1.94 | 
| 5.5 | 16.2 | 50.6 | 0.634 | 1.99 | 
| 6 | 16.5 | 51.9 | 0.650 | 2.04 | 
| 6.5 | 16.9 | 53.1 | 0.666 | 2.09 | 
| 7 | 17.3 | 54.4 | 0.682 | 2.14 | 
| 7.5 | 17.7 | 55.7 | 0.698 | 2.19 | 
| 8 | 18.1 | 57.0 | 0.714 | 2.24 | 
| 8.5 | 18.5 | 58.3 | 0.73 | 2.29 | 
| 9 | 19.0 | 59.5 | 0.746 | 2.34 | 
| 9.5 | 19.4 | 60.8 | 0.762 | 2.39 | 
| 10 | 19.8 | 62.1 | 0.778 | 2.44 | 
| 10.5 | 20.2 | 63.4 | 0.794 | 2.49 | 
| 11 | 20.6 | 64.6 | 0.81 | 2.54 | 
| 11.5 | 21.0 | 65.9 | 0.826 | 2.59 | 
| 12 | 21.4 | 67.2 | 0.842 | 2.65 | 
| 12.5 | 21.8 | 68.5 | 0.858 | 2.70 | 
| 13 | 22.2 | 69.7 | 0.874 | 2.75 | 
| 13.5 | 22.6 | 71.0 | 0.89 | 2.80 | 
| 14 | 23.06 | 72.45 | 0.908 | 2.85 |