Retirement Withdrawal Calculator
See how long a retirement balance actually lasts at a given withdrawal rate, expected return and inflation -- simulated month by month, not a single formula.
Withdrawals grow with inflation each year.
First-year withdrawal
$40,000
Balance lasts
35.8 years
Outcome
Runs out
How it's calculated
The first year's withdrawal is your starting balance times the withdrawal rate; every year after, that dollar amount grows with inflation (a level, real standard of living), while the remaining balance earns the expected return every month:
withdrawal(1) = balance × rate; withdrawal(y) = withdrawal(y−1) × (1 + inflation)
The result is a real, month-by-month simulation -- the site's one production engine -- rather than a closed-form estimate. In the special case of a flat, non-inflating withdrawal, a standard annuity- depletion formula gives an exact cross-check for how many years the balance lasts:
n = −ln(1 − i × B ÷ W) / ln(1 + i)
where B is the starting balance, W the fixed annual withdrawal, and i the annual return. On $1,000,000 withdrawing $40,000/yr (4%) at a 5% return with no inflation, that formula gives Infinity years -- checked against the simulation to the month in the site's own test suite.
Worked example
The calculator's own defaults: $1,000,000 starting balance, a 4% first-year withdrawal rate, 5% expected return, 3% inflation.
Result: the balance runs out after about 35.8 years, once withdrawals keep growing with inflation every year.
Frequently Asked Questions
How is this different from the 4% rule on the 'am I on track' page?
That page uses the 4% rule to set a savings target before retirement. This page tests a balance you already have (or plan to have) against a withdrawal rate, return and inflation assumption, to see whether it actually survives -- the reverse question, run as a real month-by-month simulation rather than a rule of thumb.
Why does inflation matter so much here?
Withdrawals in this calculator grow with inflation every year (a level real income), so a balance facing 3% inflation is drawn down faster in nominal dollars than a flat withdrawal of the same starting amount -- a real, common reason retirement balances run out sooner than a simple rate-vs-return comparison suggests.
What if my withdrawal rate is below my return rate?
Then the balance can, in principle, last indefinitely -- the growth alone can outpace withdrawals depending on the exact numbers and inflation assumption. The calculator caps its simulation at 60 years and reports "outlasts the window" rather than showing a potentially misleading exact figure for money that's effectively never depleting.
Does this model sequence-of-returns risk?
No -- it assumes the same fixed return every single year. Real markets don't; a downturn early in retirement can deplete a balance meaningfully faster than a flat average return implies, even if the average over the whole period matches. Treat this as a baseline, not a worst-case stress test.
Should I use a withdrawal rate other than 4%?
The right rate depends on how long your retirement needs to last, how much flexibility you have to cut spending in a bad market, and other income sources. A longer retirement or less flexibility generally argues for a lower starting rate; this calculator lets you test any rate against your own return and inflation assumptions rather than relying on one fixed number.
Figures on this page are estimates from the inputs you enter, not financial advice, and this site is not affiliated with any employer, plan administrator, bank or the IRS. Real accounts vary by plan rules, taxes and fees this tool doesn't model -- see the Terms.