A long time. Most people do not exceed 10 cm. It must be measured by five fingers in the palm of your hand, not by fingers from one person to another. Specifically, count from the top of the middle finger.

1, first measure the length of the third knuckle of the middle finger, such as 3 cm;

2. Measure the length of the first and second knuckles of the middle finger, for example, 4 cm;

3. Measure the distance from the lower end of the third knuckle of the middle finger to the lowest ridge of the wrist. Suppose it is 12 cm.

4. Then the standard length of the middle finger is: 3÷4× 12=9.

5, standard: any middle finger size more than 9 cm is too long; The middle finger shorter than 9 cm is too short.

6, note: be sure to measure according to the male left and female right.