HOW TO MEASURE RING SIZE ACCURATELY
Using a strip of paper, measure the circumference of your chosen finger.
Mark the meeting point of the two sides and use a ruler to check the measurement.
Remember to measure around the knuckle of your chosen finger as it is the widest part of your finger. It is best to take your measurements in the evening, as your fingers would be swollen and are the biggest at this time. Moreover, make sure to measure by pulling the strip of paper tightly around your finger to get the most accurate reading.
Of course, it is always more accurate to have your jeweler measure your ring size with specialized tools.
Below, the Ring Convention Chart allowing you to obtain your approximate ring size.