FIRE Calculator
Calculate your FIRE number using the 4% withdrawal rule.
Amortization schedule
| # | Payment | Principal | Interest | Balance |
|---|---|---|---|---|
Showing first 12 of months.
Growth over time
| Year | Invested | Value |
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Introduction
FIRE Calculator — Calculate your FIRE number using the 4% withdrawal rule. Enter Annual expenses, Withdrawal rate (%) to get an instant, accurate result.
Formula
FIRE number = annual expenses ÷ withdrawal rate, using the 4% rule (Trinity Study) by default — equivalent to annual expenses × 25.
Step-by-step
- Enter the Annual expenses.
- Enter the Withdrawal rate (%).
- Click Calculate to see your result instantly.
Real-world example
Example: With Annual expenses = 40000, Withdrawal rate (%) = 4, the FIRE Calculator gives Fire Number: 1000000, Withdrawal Rate Pct: 4.
Frequently Asked Questions
Is the 4% withdrawal rate guaranteed to be safe?
No — it's a widely referenced historical rule of thumb from the Trinity Study, not a guarantee; a lower withdrawal rate (e.g. 3.5%) is often used for extra safety margin.
What does a lower withdrawal rate do to the FIRE number?
It increases the required nest egg, since you need a larger portfolio to sustainably withdraw the same dollar amount at a lower rate.
What inputs does the FIRE Calculator need?
You'll need to provide: Annual expenses, Withdrawal rate (%). All fields use sensible defaults, so you can see a working example immediately and then adjust the values to match your own numbers.
How accurate is the FIRE Calculator?
The FIRE Calculator applies the formula exactly as calculated — FIRE number = annual expenses ÷ withdrawal rate, using the 4% rule (Trinity Study) by default — equivalent to annual expenses × 25. — so results are precise for the inputs you provide. Accuracy depends on entering correct, realistic input values.
Are these results guaranteed?
No. The FIRE Calculator gives an estimate based on the numbers you enter and standard financial formulas — actual rates, fees, taxes, and terms vary by lender, institution, and jurisdiction, and can change over time. This is not financial advice; consult a qualified financial professional for decisions specific to your situation.
Is the FIRE Calculator free to use?
Yes, the FIRE Calculator is completely free, requires no signup, and runs instantly in your browser.
About the FIRE Calculator
The FIRE Calculator uses a real, verifiable formula — FIRE number = annual expenses ÷ withdrawal rate, using the 4% rule (Trinity Study) by default — equivalent to annual expenses × 25. — so results are accurate every time, not an approximation.