Retirement Number Calculator
A retirement number is annual spending divided by the withdrawal rate you plan to take, which is why spending drives the target rather than income. Dropping the rate from 4% to 3% raises the same target by a third, so the rate is the most consequential input on the page.
The number, and the years to it
Defaults are $60,000 a year of spending at a 4% withdrawal rate, starting from 100,000 and adding $1,500 a month at 7%.
The withdrawal rate is the assumption everything else rests on, and it is not a law. It comes from studies of historical sequences over fixed horizons, and a different horizon or a different starting valuation produces a different answer.
Runs entirely in your browser. Nothing you type is sent anywhere or stored.
How the number is built
One division sets the target and one logarithm says how long the gap takes to close. The division is the important half.
Number = annual spending ÷ withdrawal rate
Notice what the formula does not ask: what you earn. Two people on very different salaries who spend the same amount have the same retirement number. Income only affects how fast the gap closes.
A worked example
Take the defaults: $60,000 a year of spending at a 4% withdrawal rate.
The number is 60,000 ÷ 0.04 = 1,500,000 — twenty-five times annual spending.
Starting from 100,000 and adding $1,500 a month at an assumed 7%, that takes 22.8 years.
Over that time you add $410,902 on top of the $100,000 you started with and the rest is growth, which is the compounding argument in one figure.
The years output is arithmetic on an assumption, not a prediction. It answers “if the account grows at 7% a year, when does it reach the target” — and no real account grows at 7% a year, it averages something while doing something else.
The rate is the biggest lever
Change only the withdrawal rate and watch the target move. At 5% the same spending needs 1,200,000. At 4% it needs 1,500,000. At 3% it needs 2,000,000.
That is a third more capital for one percentage point, because the rate sits in a denominator. Small changes there do far more than equivalent changes anywhere else on the page.
The rate is also the least knowable input. It comes from studies of historical sequences over fixed horizons — usually thirty years — and a longer retirement, a different starting valuation, or a different asset mix all change what is defensible.
“Twenty-five times your spending” and “a 4% withdrawal rate” are the same sentence. Dividing by 0.04 is multiplying by 25, and the multiple version is easier to sanity-check in your head.
Sequence risk
Two portfolios with the same average return can end very differently, because withdrawals during a fall sell more units to raise the same cash, and those units are not there for the recovery.
Of every S&P 500 trading day since 1950, 93% closed below the previous record, with the deepest fall at 56.8%, from October 2007 to March 2009, and the longest wait for a new record 7.5 years, from 1973 to 1980 — and the index still went on to new records. Something is nearly always below its high, which is the condition a withdrawal plan lives in rather than an exception to it. S&P 500 history on this page: daily closes, price only, January 1950 to September 2026.
A smooth formula cannot represent that, which is the honest limit of this calculator and the reason a plan usually carries flexibility in the spending rather than precision in the target.
Depth and duration together are what a withdrawal plan actually has to survive. Someone drawing on the index from its October 2007 peak waited until March 2013 for prices to get back there, taking withdrawals the whole way.
What erodes the target
The number is in today’s spending. At 3% inflation, $60,000 of spending in 23 years costs 118,415, so a target hit in nominal terms buys about half of what it was meant to. Either inflate the spending input or treat the assumed return as a real return, but do not mix the two. The calculator’s return input is before inflation, so at the default 7% the years output is the nominal answer; typing a return after inflation (for example 5% instead of 7%) makes the years line up with a target in today’s money, and on the defaults it stretches the wait from 22.8 years to about 28.
A fee is a withdrawal you did not choose. On this site’s arithmetic, 75 basis points a year (0.75%; a basis point is one hundredth of a percent) removes 20.2% of a thirty-year pot and 150 removes 36.5%. A 1% advisory fee against a 4% withdrawal rate is a quarter of the income.
The original data
Of the 24,971 unique videos in the search study behind this site, 17 have retire early, retirement number or how much to retire in the title, at a median of 87,636 views across 16 channels. Safe withdrawal appears in 1 at 283,990 and the millionaire target in 100 at 73,927.
A single safe-withdrawal video at 283,990 views is one of the highest medians measured on this site, and the subject has one video. The demand for the number is enormous and the supply of the arithmetic is almost nothing.
The question: The number feels impossible. Raise the withdrawal rate instead?
The answer is that raising the rate does not change what the portfolio can support, only what you plan to take from it. Moving from 4% to 6% cuts the target from 1,500,000 to 1,000,000 on paper and increases the chance the money runs out before you do. The two honest levers are spending less and saving more — and spending less moves both sides at once, which is why it dominates.
When it fails
A flat decade immediately after retiring is where this arithmetic breaks worst. Withdrawals continue, the portfolio does not grow into them, and the capital base that the whole plan assumed would recover simply does not for long enough to matter. The formula reports a number that was correct on the day it was calculated and has no mechanism for noticing that the sequence went wrong.
The second failure is a fixed retirement date. A plan with no flexibility in either the date or the spending has nothing to absorb a bad sequence.
A third is ignoring tax. Withdrawals are generally taxable and the target is gross.
A fourth is mixing nominal and real. A nominal return against today’s spending overstates badly.
A fifth is excluding one-off costs. Housing, healthcare and family expenses are not the average.
And a sixth is treating the years output as a date. It is what one assumed return implies.
Related
Safe withdrawal rate covers where the 4% came from and what it actually measured. Compound interest is the engine closing the gap. And index funds is where most of this capital sits.
What people miss is that spending is on both sides of this. Cut annual spending by 6,000 and the target falls by 150,000 at a 4% rate, while the 500 a month you are no longer spending goes into the account instead. One decision moves the finish line closer and speeds you up at the same time, which is not true of any other input here.
— Michael Whitman
This page is educational, not financial advice. Test every idea on your own charts before risking money.