This calculator estimates your FIRE number: the portfolio size that could support your expenses under a withdrawal-rate assumption.
FIRE Calculator
Calculate how much capital you would need for your portfolio to cover annual expenses using the 4% rule.
SIMULATOR
Your numbers
Recalculates instantly as you move the sliders.
ESTIMATED RESULT€540,000
ESTIMATED TIME48.7 years
CURRENT COVERAGE3.7%
WITHDRAWAL RATE4%
Estimated evolution of current wealth toward the FIRE target; the key figure is coverage versus monthly spending.
Assumption: the FIRE target uses the selected withdrawal rate (4%) and projects current wealth with a constant return; it excludes future contributions, inflation, tax and sequence risk.
Save my target of €540,000. Based on the 4% rule: an approximate target of 25 times your annual spending.
Enter monthly or annual spending, current capital and an annual return assumption. The tool estimates the target, current coverage and an approximate time path.
It applies the 25x rule, equivalent to a 4% withdrawal rate: target equals annual spending multiplied by 25. The time estimate projects current capital toward that target.
With spending of $2,000 per month, annual spending is $24,000. The 25x rule gives a FIRE number of $600,000.
The FIRE number is highly sensitive to spending. Lower recurring expenses reduce the target proportionally. Variants such as Coast FIRE or Barista FIRE use more flexible assumptions.
Common mistakes are treating the 4% rule as certainty, underestimating real expenses and forgetting taxes on withdrawals.
Assumptions: the time estimate does not include future contributions and the 4% rule is historical guidance, not a guarantee.
CNMV — Investor Education · Bank of Spain — Financial Education
FIRE Calculator, with context
What is the 4% rule?
A historical rule of thumb for withdrawing around 4% of a diversified portfolio in the first year and adjusting for inflation.
Is it reliable?
It is a guide, not a guarantee. Some investors use lower rates for longer horizons or lower expected returns.
Does FIRE mean never working again?
Not necessarily. Some versions combine portfolio income with flexible or part-time work.
Does it include taxes?
Include withdrawal taxes in your spending estimate.
Illustrative results for educational purposes · Educational information, not financial advice.