How your retirement paycheck is calculated

Your retirement paycheck is the highest monthly amount, after tax, that your savings can produce and still last to your planning age (95 unless you change it) in 90% of simulated retirements.

Here's how that number is found. MangoDime builds 5,000 versions of your retirement. For each one, every year's market return is drawn from real U.S. history — 1928 through 2025, using the S&P 500's total return and the 10-year Treasury — and blended by your stock/bond mix. Your balances grow or shrink with those returns, your contributions are added until you retire, and from retirement on, your spending, Social Security, pension, taxes, and required distributions play out year by year. Then the simulation searches for the largest monthly spending level that survived in 9 out of 10 of those 5,000 runs. That's your paycheck.

Because the returns are drawn from real years rather than one average, a bad stretch early in retirement shows up in the result — the thing a straight-line calculator can't see.

Everything is in today's dollars. The simulation removes inflation from each year's return before compounding, so a $4,100 paycheck means what $4,100 buys now.

Same inputs, same answer: the simulation is seeded from your inputs, so it doesn't drift between visits or devices.