Measuring finger to determine "ring size" is important. Knowing your ring size allows you to purchase the jewelry with confidence even if don't have the option of trying it on beforehand. This is especially true if you want to "buy jewelry online". Your ring should fit your finger comfortably - snug enough so that it will not fall off, but loose enough to slide over your knuckle.
To measure your finger, wrap either a strip of paper or string around your finger’s base, below your finger’s joint and near your knuckle. Mark the place where the paper or string overlaps and forms a circle. With a ruler, measure the section up to the mark. The following are measurements for the United States and Canada and their coinciding
ring sizes:
Size 1 is equal to 40.8 mm or 1.61 inches
Size 2 is equal to 41.9 mm or 1.65 inches
Size 3 is equal to 44 mm or 1.73 inches
Size 4 is equal to 46.5 mm or 1.83 inches
Size 4.5 is equal to 47.8 mm or 1.89 inches
Size 5 is equal to 49 mm or 1.93 inches
Size 5.5 is equal to 50.3 mm or 1.98 inches
Size 6 is equal to 51.5 mm or 2.03 inches
Size 6.5 is equal to 52.8 mm or 2.08 inches
Size 7 is equal to 54 mm or 2.13 inches
Size 7.5 is equal to 55.3 mm or 2.18 inches
Size 8 is equal to 56.6 mm or 2.23 inches
Size 8.5 is equal to 57.8 mm or 2.28 inches
Size 9 is equal to 59.1 mm or 2.33 inches
Size 9.5 is equal to 60.3 mm or 2.37 inches
Size 10 is equal to 61.6 mm or 2.43 inches
Size 10.5 is equal to 62.8 mm or 2.48 inches
Size 11 is equal to 64.1 mm or 2.52 inches
Size 11.5 is equal to 65.3 mm or 2.57 inches
Size 12 is equal to 66.6 mm or 2.62 inches
Size 12.5 is equal to 67.9 mm or 2.67 inches
Size 13 is equal to 69.1 mm or 2.72 inches
Warnings and Tips to Measure Ring Size :
• Men’s and women’s ring sizes are exactly the same.
• Half sizes are for those whose measurements fall in between whole numbers.
• The best time of day to measure your finger is late afternoon or evening, because your fingers swell. Finger size changes depending on the time of day and the weather. For best results measure your finger size at the end of the day and when your fingers are warm. Fingers are smaller in the early morning and when cold. Measure finger size 3 to 4 times will be better to eliminate an erroneous reading. Avoid using string or paper to measure ring size as these materials can stretch or twist, yielding an inaccurate measurement.
• If you want to be completely certain that you have your ring measurement correct, then you should go to a local retailer, such as Walmart or Target, and have the clerk at the
jewelry counter measure your finger for you. They will tell you your size without pressuring you to buy anything, whereas if you go to a jewelry store to get your measurement, they will persistently try to sell you rings.
For the most accurate reading, measure the finger at the end of the day when the finger is the largest. After sliding the ring sizer on, make sure it slides off fairly easily over the knuckle, and remembers do not measure cold fingers because this is when fingers are their smallest. Although, in most cases, you can have a ring re-sized by a jeweler after it has been purchased, it's still a smart idea to know what your "ring size" is before exchanging money.