🏖️ Retirement Calculator

Project the size of your retirement nest egg from what you have today, what you add each month, an expected annual return, and how many years you have left to grow it.

Two future values added together

What you already hold and what you add each month grow differently, so they are projected separately. With i the monthly return (annual / 12) and n the months to retirement:

lump sum      = current x (1 + i)^n
contributions = monthly x ((1 + i)^n - 1) / i
nest egg      = lump sum + contributions

The second line is the ordinary annuity formula, so each deposit is treated as landing at the end of its month. On the defaults - $20,000 today, $500 a month, 7%, 30 years - the lump sum becomes $162,330 and the contributions $609,985, for $772,315. You put in $200,000 of that; the other $572,315, roughly 74%, is growth.

Starting date beats contribution size

Run the same $500 a month for 20 years instead of 30 and the projection falls to $341,238. Waiting a decade costs $431,077, though you only skipped $60,000 of deposits - the missing money is the compounding those first ten years of deposits would have done for the next twenty. Doubling to $1,000 a month for those 20 years only reaches $601,701, still short of the 30-year figure.

This is a pre-tax number in future dollars. At 3% inflation $772,315 in thirty years buys what $318,184 buys now. If you want the answer in today's money, enter a real return - about 4% rather than 7%.

Frequently asked questions

How much income will my nest egg produce?

The common planning rule is to withdraw 4% in the first year and adjust it for inflation after that. On $772,315 that is $30,893 a year, or about $2,574 a month, before tax and before any Social Security.

What return should I assume?

7% is the usual stand-in for a long-run stock-heavy portfolio before inflation. Lower it as you approach retirement and shift into bonds, and subtract any fund expense ratio - 0.5% in fees comes straight off the 7%.

Does it matter that the projection assumes a steady 7%?

For the total, not much; for the timing, yes. Real returns arrive unevenly, and a bad run in the first few years of retirement hurts far more than the same run at the end. Treat the figure as a midpoint, not a promise.