Knowing at least approximately when you’re going to die will help you make much better decisions about earning, saving, and spending. So I urge you: Go ahead and try a life expectancy calculator. You might be wondering which particular calculator to use. I posed this question to the Society of Actuaries, since they’re the real experts. They wouldn’t endorse a certain calculator but instead referred me to their own Web site (soa.org), which mainly provides tools for professional actuaries.