FIRE Calculator
Estimate a financial-independence target and the time to reach it using a configurable planning withdrawal rate.
Content updated August 2, 2026
| Time | Contributions | Growth | Balance |
|---|---|---|---|
| 1 year | $24,000.00 | $5,545.16 | $129,545.16 |
| 5 years | $120,000.00 | $43,255.63 | $263,255.63 |
| 10 years | $240,000.00 | $131,615.79 | $471,615.79 |
| 15 years | $360,000.00 | $277,542.01 | $737,542.01 |
| 19 years | $456,000.00 | $446,279.61 | $1,002,279.61 |
Planning estimate in today's money. It does not simulate volatile returns, retirement withdrawals, taxes, fees, pensions, benefits, health costs, or longevity.
Financial independence planning starts by connecting future spending to a portfolio target. This calculator divides annual spending by a user-selected planning withdrawal rate, then projects how the current portfolio and end-of-month contributions could move toward that target.
The return input is a real annual return, meaning after inflation, so annual spending and the target remain in today's currency. The result is a transparent scenario rather than a promise that a particular withdrawal rate or retirement date will work.
The FIRE formula
Target = E ÷ w; i = (1+R)^(1/12)−1; Bₘ = Bₘ₋₁(1+i)+CE = annual spending in today's currency · w = user-selected planning withdrawal rate · R = effective annual real return · i = equivalent monthly real return · C = end-of-month contribution · B = invested portfolio.
Worked example
With $40,000 of annual spending and a 4% planning rate, the modeled target is $1,000,000. Starting at $100,000, adding $2,000 each month, and earning a constant 5% real annual return reaches the target in 228 months, or 19 years, with a modeled ending balance of about $1,002,279.61.
Assumptions, rounding, and limitations
Assumptions
- Annual spending is constant in today's purchasing-power units.
- The entered return is an effective annual real return converted to an equivalent monthly rate.
- The same contribution is deposited at each month end until the target is reached.
- The planning withdrawal rate is a user assumption and is not represented as safe, guaranteed, or suitable.
- All money inputs and outputs use the selected currency unit.
Rounding: The monthly projection retains floating-point precision. Time is reported as the first whole month whose ending balance reaches the target, while displayed currency uses up to two decimal places.
Limitations
- Supports amounts up to 1 trillion, withdrawal rates from 0.1% to 100%, annual real returns above -100% through 100%, and projections up to 100 years.
- Does not simulate volatile returns, sequence risk, retirement withdrawals, changing contributions or spending, taxes, fees, asset allocation, pensions, government benefits, health costs, or longevity.
- The result is a planning scenario, not individualized retirement, investment, tax, or legal advice.
Sources
- Managing Lifetime Income — Investor.gov, U.S. Securities and Exchange Commission
- Compound Interest Calculator — Investor.gov, U.S. Securities and Exchange Commission
- How Fees and Expenses Affect Your Investment Portfolio — Investor.gov, U.S. Securities and Exchange Commission
How the FIRE target and timeline work together
The target is annual spending divided by the planning withdrawal rate. A lower rate produces a larger target; a higher rate produces a smaller one. The rate is not selected or certified by the calculator.
The portfolio projection converts the effective annual real return to an equivalent monthly rate. Each month applies growth to the opening balance and then adds the entered contribution, stopping when the balance first reaches the target or the 100-year model horizon ends.
Why a withdrawal rate is a scenario, not a safety claim
Actual retirement portfolios experience uneven returns, and poor returns early in retirement can affect how long savings last. Longevity, asset allocation, taxes, fees, benefits, changing spending, and future inflation also matter.
Investor.gov notes that defined-contribution account holders bear investment risk and have no guarantee that a balance will be adequate for retirement. Test multiple rates and returns, include fees in the return assumption, and review the plan as circumstances change.
Frequently asked questions
▶How is the FIRE target calculated?
Annual spending is divided by the entered planning withdrawal rate. For example, $40,000 divided by 4% produces a $1,000,000 scenario target.
▶Does the default 4% rate mean 4% is safe?
No. It is an editable example only. The calculator does not select a safe rate or model the probability that a portfolio survives a particular retirement length.
▶Why does the calculator use a real return?
A real return is after inflation, which lets the annual spending input and target stay in today's purchasing-power units.
▶When are monthly contributions added?
The model applies that month's real investment return first and adds the contribution at month end.
▶What does more than 100 years mean?
The entered scenario did not reach its target within the calculator's 1,200-month limit. It does not mean the target can never be reached under different assumptions.
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Open calculator →Disclaimer: FIRE Calculator results are estimates for general information and education only, and are not financial, tax, legal or medical advice. Verify important decisions with a qualified professional.