One reason people buy term insurance is for income replacement for their families.
A rule of thumb is that a 15x to 20x multiples of your annual income, depending on how close you are to retirement, is an appropriate amount of coverage to have according to many financial advisors.
The rule of thumb applied:
If you earn $50,000 of income a year, and are 35 years old. (30 years to retirement). 20 times $50,000 is 1 million of coverage that should be applied for at the very minimum.