Finance

FIRE calculator

The capital you need — and in how many years.

  • Instant
  • Free
  • Private (processed locally)
  • No sign-up
Target capital (FIRE number)
Reached in

Your freedom has a price — compute it

Financial independence is not a lottery: it is an equation with three variables — your expenses, your savings, your return. Enter them: the tool shows your FIRE number (target capital) and the years to reach it, recomputed with every slider.

  1. Expenses first

    THE master variable: every dollar of monthly spending removed cuts the target capital by $300 (at 4%).

  2. Withdrawal rate

    4% is the classic; 3.5% or 3% for a very long retirement or extra caution.

  3. Your trajectory

    Current capital + monthly savings + return: the simulation gives the arrival year.

FIRE number by expenses (at 4%)

Monthly expensesAnnual expensesTarget capital
$1,500$18,000$450,000
$2,000$24,000$600,000
$3,000$36,000$900,000
$4,000$48,000$1,200,000

The 4% rule comes from studies of 20th-century US markets: a robust landmark, not a guarantee. Diversification, withdrawal flexibility and a safety margin remain your best allies. This is not investment advice.

Frequently asked questions

What is the 4% rule?

Born from the Trinity study (1998), it observes that a diversified portfolio has historically sustained an annual withdrawal of 4% of its initial value, inflation-adjusted, for 30 years with a high success rate. Hence the formula: target capital = annual expenses × 25.

Why is my “FIRE number” 25 times my expenses?

Because 1 ÷ 4% = 25. With $2,000 of monthly expenses ($24,000/year), you need $600,000. A more cautious 3.5% withdrawal rate raises the multiple to about 28.6; 3% to 33.3.

Is the years calculation reliable?

It is a constant-return simulation — reality will be messier. It still shows the right order of magnitude and above all the sensitivity to parameters: saving more accelerates far more than chasing higher returns.

Does FIRE mean quitting work?

Not necessarily: FIRE (Financial Independence, Retire Early) spans variants — Lean FIRE (frugal), Fat FIRE (comfortable), Barista FIRE (chosen part-time), Coast FIRE (let it compound). The common point: work becomes a choice, not an obligation.