How we compute your life expectancy

We start with "life tables", which contain your base chance of dying each year. The life tables are for typical Americans doing typical amounts of exercise, smoking, driving, etc. We modify the base chances to fit your own personal health habits. This gives your chance of dying at each age, and hence of living living one more year. Averaging (summing the probability of living to each age times that age) gives your "life expectancy".

Our page also gives you a 50% coverage interval for when you might die. If you are in the unlucky 25% of the people who are similar to you in health habits, you will die before the lower age. If you are in the top 25%, you will live past the older age point.

The math is not hard.

For activities like driving, it is fairly easy to get reliable numbers on how they effect your chance of death. The entire auto insurance industry makes sure this information is accurate! But, for other things, like exercise, or anti-oxedents, it is much more difficult to get reliable data. It is these numbers that are hard to come by and where we need your help!