How to measure the inner diameter
You can take a ring that fits you well in size and measure it with a ruler in the central part of it. Keep in mind that you must measure the inside part.
How to measure the length
1. Take a strip of thin paper or string and wrap it around the finger you want to measure.
2. Check that the strip of paper / thread can go in and out of the knuckles.
3. Cut the strip of paper/thread and measure it. 4. You now have the length in mm.
Aspects that we must take into account when choosing the size of the ring:
1. Often we do not carry the same size on the left hand as on the right.
2. The temperature influences when taking measurements of the finger. The hotter, the more swollen they are.
3. The size may vary depending on the time of year: in summer the hands swell a little.
4. The thicker the ring, the more size you have to take. If you are between sizes and choose a chubby ring, take the large size.