FIRE & Coast FIRE Calculator
Calculate your Financial Independence number and when you can stop saving.
Your Situation
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Assumptions
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Your FI Number $1,000,000
Coast FIRE Age 38
Projected FI Age 49
Years to Full FI 19
Real Return 3.9%
Current Progress10.0%
$100,000$1,000,000
At your current rate, you'll reach Coast FIRE at age 38.
Coast FIRE means your current savings alone will compound to your FI Number by retirement age — no more saving needed.
Milestone Projection
| Age | Portfolio | Status |
|---|---|---|
| 30 | $100,000 | Saving |
| 35 | $247,653 | Saving |
| 38 | $363,425 | Coasting |
| 40 | $454,743 | Coasting |
| 45 | $745,199 | Coasting |
| 49 | $1,059,722 | FI Reached |
Methodology
FI Number = Annual Spending ÷ SWR. Coast FIRE is the point where your current portfolio, growing at the real return rate, will reach your FI Number by retirement age without additional contributions. Projection uses real returns (Fisher equation) for inflation adjustment. This is a deterministic model — real results depend on sequence of returns, taxes, and spending variability.
💬 Frequently Asked Questions
FIRE stands for Financial Independence, Retire Early. It's a movement focused on aggressive saving and investing (typically 50-70% of income) to build enough wealth to live off investment returns, allowing retirement decades before the traditional age of 65.
Your FIRE number is your annual expenses multiplied by 25 (based on the 4% rule). If you spend $40,000/year, your FIRE number is $1,000,000. For Lean FIRE (minimal spending), multiply by 25. For Fat FIRE (comfortable lifestyle), use your desired spending level.
Coast FIRE is when you've saved enough that compound growth alone will reach your full FIRE number by traditional retirement age (e.g., 65), even without additional contributions. At Coast FIRE, you only need to earn enough to cover current expenses — no more saving required.