Mahakali jewellers provides a ring size chart that you can use to find your ring size based on your measurements.
Step 1: Mark the spot where the paper/Thread meets
Step 2: Wrap the paper/Thread around your finger.
Step 3: Cut a thin strip of paper or Thread
Step 4: Measure the length of the thread with your ruler.
The chart includes both the US and UK ring sizes. Simply find the measurement that matches your finger and look up the corresponding ring size on the chart.
This is a chart that will be extremely helpful for you to determine the ring size that you need. You can either make use of a tape or a small piece of string to measure the area that will be occupied by the ring.