LDFerguson has put it aptly. There is no simple formula for working out how much is enough. Everyone's needs differ as per their lifestyle and financial responsibilities. To come to a more accurate figure, make note of all the expenses that your family may need to bear in case of your death - loan and mortgage payments, daily living expenses, education expenses, and even seemingly minor expenses such as child care costs.
Online life insurance calculators will help you estimate the amount of life insurance you need.
If you are in your 30's most insurance experts, recommend aiming for a death benefit of 10 - 15 times your current annual income.
Denise at AccuQuote
Disclaimer: I work for AccuQuote and this is my personal opinion.