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Calculator

FIRE calculator

The FIRE (Financial Independence, Retire Early) movement centres on saving aggressively to reach 25× annual expenses invested. This calculator projects your timeline.

Updated July 2026
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FI target (25× spending)
$1,200,000
Years to FI
17.9 years

How it works

Years to FI ≈ ln(1 + FI_Target × r / (Contribution × 12)) / ln(1 + r) — solving compound growth for the retirement number
  • FI target = 25 × your annual spending (based on the 4% rule).
  • Projected balance compounds your current savings plus monthly contributions at your expected real return.
  • Years to FI is when projected balance meets or exceeds target.
  • Coast FIRE: the age at which existing savings alone, with no further contributions, reach the target by traditional retirement age.

Worked examples

  • $40k spending, $200k saved, $2,000/month contribution, 7% real: about 14 years to FI.
  • Same person saving $3,000/month: about 11 years.
  • Cutting expenses from $40k to $32k (raising saving rate) cuts several more years off the timeline.

Frequently asked questions

What is FIRE?

A movement focused on saving 40–70% of income and investing in diversified index funds to reach 25× annual expenses invested — making paid work optional decades before traditional retirement.

Is FIRE realistic?

Full FIRE is hard on average incomes. Coast FIRE — investing enough early that you never need to add more — is much more achievable and delivers most of the optionality.

What return should I assume?

Use real returns (after inflation). US stocks have averaged about 7% real long-term; balanced portfolios 4–6%. Being conservative reduces the risk of over-planning.

Related

FIRE (glossary)
Definition and variants.
Financial freedom guide
The calm milestone-based path.
Retirement calculator
Traditional retirement projections.
Educational information only. Not personalised financial advice. Consult a qualified professional for decisions specific to your situation.