About the Retirement Longevity Calculator
The biggest fear in retirement is outliving your money. This calculator draws your balance down month by month at your withdrawal amount — growing withdrawals with inflation and the balance with returns — to show how many years it lasts.
How it’s calculated
Each month the balance earns its return and the (inflation-growing) withdrawal is subtracted, repeated until the balance reaches zero.
Example calculation
$800,000 with a $4,000 monthly withdrawal at a 5% return and 2.5% inflation lasts roughly 21–22 years.
Frequently asked questions
Why does inflation matter so much?
Because your withdrawals must grow to keep the same buying power, later withdrawals are larger in dollar terms — which drains the balance faster than a flat withdrawal would suggest.
What withdrawal rate is sustainable?
A starting withdrawal around 4% of the balance has historically lasted ~30 years. Higher rates run out sooner, especially if early returns are poor.
Retirement projections are estimates based on the assumptions you enter and do not guarantee future outcomes. Contribution limits and tax rules change over time — verify current figures and consider speaking with a financial professional.