Your savings rate — the percentage of take-home pay you save — is the single most powerful variable in FIRE planning. More than your salary, your investment choices, or your city. See yours and how it maps to a retirement timeline.
At a 10% savings rate, you need to work 43 years to retire. At 50%, you need just 17 years. At 75%, just 7 years. The relationship is non-linear — small increases in savings rate compress your timeline dramatically, especially as you approach 50%.
This is based on the "shockingly simple math" behind FIRE from Mr. Money Mustache: your years to retirement is determined entirely by your savings rate and expected investment returns. Your income level cancels out — a doctor saving 10% has the same FIRE timeline as a teacher saving 10%.
The 4% rule (safe withdrawal rate) is used here to calculate your FIRE target: 25× your annual expenses. Investment returns are modeled at 7% annually (inflation-adjusted S&P 500 historical average).