How long is a Jewish generation?

Answer 1

The older definition of a "generation" (the average interval between the birth of an individual and the birth of its offspring) was 20 or 25 years.

However, genealogical studies have revealed that this is too simplistic and can result in large inaccuracies during statistical calculation.

According to Ancestry.com, a calculation based upon "three generations per century (33 years each) for male lines and 3.5 generations per century (29 years each) for female lines" leads to much more accurate estimates.

Answer 2

A Jewish generation is no different form any other generation. A generation is the time from the birth of one person to the birth of that person's child. that has been roughly been considered to be 20-25 years, but more recently, with many people having children later in life, the period has been increasing and for the late 20th Century in developed countries may be considered to be 30 or even 35 years.