FIRE Calculator

Your income barely matters. Your savings rate is everything.

This is the part people refuse to believe, so here it is plainly: if you start from zero, the time it takes to reach financial independence does not depend on your income at all. It depends only on the percentage of it you keep.

The reason is that income sits on both sides of the equation. Earn twice as much and save the same share, and you save twice as much each year — but you also spend twice as much, so the target you are aiming at is twice as large. The two cancel exactly. Someone saving 40% of $60,000 and someone saving 40% of $600,000 arrive on the same day, holding wildly different amounts of money.

At a 7.1% real return. The curve is steepest where most people live: going from saving 10% to 20% removes about 10 years, while going from 60% to 70% removes about 3. The first cuts to your spending are worth far more than the last ones.

Is the 4% rule actually safe? We tested it.

Every FIRE calculator on the internet multiplies your spending by 25 and stops there. The 25 comes from a 4% withdrawal rate, and that rate is an assumption — so rather than repeat it, we ran it against the record. Each complete 30-year retirement since 1871, all 1507 of them, withdrawing 4% of the starting portfolio in year one and raising that amount with inflation every year after, whatever the market did.

It survived 97.9% of them. The failures are not scattered: the worst retirement to begin in the entire record started 1929-09, and that portfolio ran dry after 16.6 years.

The other tail is the one nobody talks about. The median outcome was ending with 3.17× the starting portfolio, after inflation, after thirty years of withdrawals. The typical failure mode of the 4% rule is not running out of money. It is dying with several times what you retired on, having under-spent your whole retirement.

And the longer the retirement, the harder it is to fund — which matters more for early retirement than for a conventional one, because the horizon can be fifty years rather than thirty:

What this test is not

This is 100% US large-cap stocks. The Trinity study and its descendants model stock-and-bond mixes, and bonds change the answer — they trim the upside and soften the worst sequences. The record committed to this site has no bond series, and rather than invent one, the page tells you which question it answered: what an all-stock portfolio did, before fees and before taxes.

It is also, unavoidably, US history — one country’s unusually good century and a half. And a survival rate is not a probability. 97.9% does not mean your retirement has a 97.9% chance; it means that of the retirements that have already happened, that share worked out. The future is not a draw from that hat.

Where the number comes from

The default return here is measured, not chosen. Across the whole record from 1871 to 2026-07, US large-cap stocks returned 7.1% a year after inflation with dividends reinvested — the same figure the investment backtest reports, computed by the same engine. Because it is a real return, the target is already in today’s money and there is no separate inflation input. If you want to see what inflation does to a fixed sum over a long retirement, the inflation calculator runs on the same CPI series.

A single average return also hides the thing that decides early retirements. Two portfolios can earn the same average and end in completely different places depending on the ORDER of the returns — a bad first decade is very hard to recover from once you are withdrawing. That is exactly why the survival test above exists, and why a smooth projection cannot answer the question on its own. The rolling returns study shows how wide the spread has been.

Common questions