Your savings rate predicts your retirement date more powerfully than your income, your return, or almost anything else. Here is exactly why, and exactly what yours means.
// your savings rate
0%
of take-home income saved and invested
—
10%
Typical
25%
Strong
50%
Aggressive
70%
Extreme
Your numbers
Annual take-home income$75k
Annual expenses$52k
Savings rate = (income − expenses) / income. Use take-home (after-tax) figures for both.
Refine the estimate (optional)
Current age30
Current portfolio$0
Real return (after inflation)5%
Withdrawal rate4%
Annual savings
$0
Years to FI
—
FI age
—
FI number
—
Years to FI by savings rateYour rate
Why this curve bends so hard
Going from 10% to 25% savings barely moves your date. Going from 50% to 65% saves years per percentage point. That is because a higher savings rate does two things at once: you save more and you need less (your expenses, and therefore your target, shrink too). The curve is steepest exactly where most people assume it flattens out.
⚠️ Educational estimate only, not financial advice. The years-to-FI curve assumes a constant savings rate and constant real return the entire time, starting from your current portfolio. Real life has raises, setbacks, and market swings that this simplification does not capture.
How this calculator works
Savings rate is simply (income − expenses) / income. The years-to-FI figure solves for how long it takes a portfolio, growing at your real return with annual contributions equal to your savings, to reach expenses / withdrawal rate — the classic FIRE number.
The curve on the right is a well-known relationship in the FIRE community: at a given real return and withdrawal rate, years-to-FI depends almost entirely on your savings rate, not your income level. A person earning $50,000 and saving 50% reaches FI in roughly the same number of years as someone earning $500,000 saving the same 50% — because both the contribution and the target scale with income at the same rate. Only the savings rate itself changes the curve.
What is a good savings rate?
The average American saves under 10% of income. Anything above 20% is considered strong. The FIRE community often targets 50%+ specifically because of how sharply the years-to-retirement curve bends once you cross that point — each extra percentage point saves disproportionately more time than the one before it.
Why does savings rate matter more than income?
Because your FIRE number is based on your expenses, not your income. A high earner who spends everything they make needs just as large a portfolio as anyone else at that spending level, and has the same zero years of progress toward it. Someone earning far less but saving half their income builds both a smaller target and a real contribution engine at the same time.