Accurately measuring your finger for its ring size is pretty simple. There is a standard North American conversion scale, and the same scale is used for both men and women. Note that it's best to measure your finger later in the day; fingers do swell a bit and you might have trouble removing a ring if you don't take this into account when sizing it.
Cut a thin strip of paper.
Wrap the paper around your finger. Make sure the paper is below the joint of your finger and close to your knuckle.
Mark the spot where the paper meets and measure the distance with your ruler.
Use the following chart to determine your ring size. Rings also come in half sizes, the measurements of which, of course, will fall somewhere in between the whole sizes.
Size 4: 1 13/16 inches Size 5: 1 15/16 inches Size 6: 2 1/16 inches Size 7: 2 1/8 inches Size 8: 2 1/4 inches Size 9: 2 5/16 inches Size 10: 2 7/16 inches Size 11: 2 9/16 inches Size 12: 2 5/8 inches Size 13: 2 3/4 inches Size 14: 2 7/8 inches
If you're still in doubt, download a printable ring size chart. Many online jewelers offer these, and their charts might be slightly more accurate for their particular rings.
Alternatively, go to the jewelry counter at your local discount retailer, such as K-Mart, Target or Walmart. You'll get a fitting without the pressure to buy that comes with going to a jewelry store.
Printable ring size charts can help you surprise a loved one — you simply match an existing ring to the circle representing the correct ring size.