How long does it take an eyebrow to grow fully back?

A general fact is that the eyebrows hair growth cycle is very short when compared to the cycle of head hair. However, the eyebrows hair grows very slowly, approximately it grows 1/3 rd as fast as the growth of head hair. 0.16mm is the average rate of eyebrow hair growth per day. This is slower than the hair growth on the thigh, which has 0.25mm as the average hair growth per day.

Hair growth in any region of the body usually depends on the health and age of the person. For mature adults and pre-pubescent children, the shortest period of eyebrow hair growth is 56 and 58 days respectively. The longest period to replacement of eyebrow hair for pubescent children is 65 days and for mature adults in the retirement age is 73 days.

The eyebrow replacement period for those who pluck or thread the eyebrows is about 56 days (nearly 2 months). The re-growth period after shaving is the toughest thing to find out. Once the hair falls out due to shaving, the hair growth cycle will starts again from the scratch.