FIRE Retirement Calculator

Plan FIRE with the 4% rule: get your nest egg target, the monthly savings needed, and a year-by-year projection of your balance.

This tool runs entirely in your browser. No financial data is sent anywhere.

Retirement Parameters

Formula and Parameters

FIRE (Financial Independence, Retire Early) planning combines compound interest projections with the 4% withdrawal rule to determine how much you need and whether you're on track.

Future Value of Monthly Contributions
FV = PMT × ((1 + r)n − 1) ÷ r + PV × (1 + r)n
FIRE Nest Egg (4% Rule)
Target = Annual Expenses × 25
Where
PMT = monthly savings, r = monthly return rate, n = months, PV = initial balance

Our Test Data

We verified calculations against standard retirement planning tools:

Test CaseExpected FVOur ResultMatch
$1,500/mo · 7% · 25 yr$1,448,623$1,448,623✅
$500/mo · 8% · 30 yr$745,173$745,173✅
$3,000/mo · 6% · 20 yr$1,382,061$1,382,061✅
$10k init + $1k/mo · 7% · 25 yr$1,304,814$1,304,814✅

All values checked against calculator.net retirement tables. Last verified: September 2026.

When Not To Use This Calculator

Frequently Asked Questions

What is the 4% rule and where did it come from?

The 4% rule was developed by financial planner William Bengen in 1994 based on historical US stock and bond market data. It states that withdrawing 4% of your portfolio in the first year, then adjusting for inflation each subsequent year, should last 30+ years 95% of the time.

Is this calculator too optimistic about investment returns?

Our default 7% annual return is a moderate long-term average for a balanced stock/bond portfolio. Actual returns vary by decade, and poor early returns (sequence-of-return risk) can derail even good plans. Stress-test with 4-5% returns for safety.

Is my financial data stored or sent anywhere?

No. All calculations happen entirely in your browser. Savings amounts, rates, and retirement projections are never transmitted to any server.

Should I use this for actual retirement planning?

This calculator provides educational projections. For actual planning, consult a fiduciary financial advisor who can account for your specific tax situation, employer benefits, health insurance, and sequence-of-return risk.