FIRE Calculator
Financial Independence Is a Multiple of Your Spending, Not Your Income
The FIRE (Financial Independence, Retire Early) movement reduces retirement planning to one number: how much invested wealth do you need so that a safe withdrawal rate covers your annual expenses indefinitely. That number depends only on spending and your chosen withdrawal rate — not on income directly — which is why two people earning the same salary can reach financial independence years apart depending on how much they spend.
The Formula
Years to reach that number are solved from the standard future-value-of-savings equation, using your current savings, annual contributions, and expected return until the projected balance equals the FIRE number.
Where This Calculation Matters
- Setting a savings rate target — because the FIRE number scales directly with spending, cutting expenses shrinks the target and shortens the timeline simultaneously.
- Choosing a withdrawal rate — a 4% withdrawal rate implies a FIRE number of 25 times annual expenses; a more conservative 3.5% implies roughly 28.6 times.
- Comparing career and lifestyle tradeoffs — the years-to-FIRE output makes the cost of lifestyle inflation concrete: higher spending both raises the target and slows the contributions needed to hit it.
- Milestone tracking — re-running the calculation periodically as savings and expenses change shows whether the timeline is improving or slipping.
Savings Rate Drives the Timeline More Than Return Rate
| Savings rate | Years to FIRE |
|---|---|
| 10% | 41.7 |
| 20% | 30.7 |
| 30% | 24.0 |
| 40% | 19.0 |
| 50% | 15.0 |
| 60% | 11.4 |
| 70% | 8.3 |
Figures computed from the calculator's own formula at a 7% return and 4% withdrawal rate; actual results depend heavily on your real return and starting balance.
How to Use This Calculator
- Enter your annual expenses in retirement.
- Enter your current investable savings.
- Enter your annual savings or contributions.
- Enter your expected annual return rate.
- Enter your target withdrawal rate, or leave the 4% default.
- Select Calculate to see your FIRE number and the estimated years to reach it.
Related Calculations
If you plan to keep some income coming in during retirement, try the Barista FIRE Calculator, or check how much you'd need today with no further contributions using the Coast FIRE Calculator.