Traditional retirement
“If I retire at the age I chose, does the portfolio last to my end age?” The result reports whether it lasts, what remains, or the age at which it is depleted.
How to read the retirement & FIRE calculator
Use one monthly retirement model to test a chosen retirement age, solve for financial independence, find when contributions could stop, or see how part-time income could bridge an earlier exit from full-time work.
What it calculates
The calculator follows a portfolio from the current age to the plan end age. Before retirement it adds contributions and applies the working return. After retirement it applies a possibly different return, subtracts spending, and includes optional part-time income, pension or Social Security, withdrawal tax, and scheduled cash flows.
All four modes run that same state machine. Traditional retirement tests an age you supply; FIRE and Barista FIRE solve the earliest age the remaining plan can support; Coast FIRE solves the earliest age contributions can stop while growth still reaches the required portfolio at the desired retirement age.
Strategies and questions
FIRE
“What is the earliest age this portfolio can support my retirement spending with no more salary or contributions?” Every candidate age is tested through the plan end, not merely against a fixed account multiple.
Coast FIRE
“When could I stop contributing but continue working until my desired retirement age?” After the solved coast age, the existing portfolio grows without regular contributions toward the portfolio required at retirement.
Barista FIRE
“How early could I leave full-time work if part-time income covers part of spending?” The portfolio supplies the after-tax monthly gap until the part-time end age. Both spending styles include that timing when solving the required portfolio and age.
Lean FIRE and Fat FIRE are not separate engines or switches. They are ordinary FIRE scenarios with lower or higher retirement spending. Comparing scenarios makes the tradeoff visible without changing the calculation method.
Fixed spending or a percentage withdrawal rule
A fixed amount
You choose annual or monthly spending. With inflation adjustment on, the cash withdrawal rises to preserve the entered purchasing power. With it off, the nominal cash amount stays flat and buys less over time.
The percentage withdrawal rule
The first withdrawal is a percentage of the portfolio on the day retirement starts. That initial dollar amount then rises with inflation; the calculator does not keep taking the same percentage of whatever balance remains each year.
Major inputs
- Current, retirement, and end ages
- The current age starts the plan. The desired retirement age is tested directly in Traditional mode and is the destination in Coast mode. The end age is the longevity horizon every strategy must cover.
- Current investments
- The portfolio available at the start. The page treats it as one pool; it does not apply account-specific access, tax, or required-distribution rules.
- Annual contributions
- Total regular saving from all sources, in today's money. It rises with inflation while working and stops at retirement or at the solved Coast FIRE age.
- Working and retirement returns
- Separate steady annual assumptions before and after retirement. A more conservative retirement allocation can be represented with a lower drawdown return.
- Desired retirement spending
- The after-withdrawal-tax amount available to spend, expressed in today's money. Under the percentage rule it also sets the portfolio target the chosen rate must support.
- Withdrawal rate
- The share of the retirement-date portfolio used to set the first annual withdrawal. Four percent is a historical rule of thumb to test, not a safe rate for every horizon, asset mix, fee, or future market.
- Inflation
- Raises today's-money cash flows as time passes and discounts future nominal values back to current purchasing power.
- Part-time income
- Used only in Barista FIRE and restated with inflation. It reduces the monthly amount the portfolio must supply until the entered age, including in percentage-rule target and age solving.
- Pension or Social Security
- Optional continuing income beginning at a chosen age. It lowers a fixed-spending requirement, but the percentage-rule solver does not net it against the FIRE number. Use an official Social Security benefit estimate rather than an unsupported assumption.
- Tax and extra cash flows
- The optional flat tax applies to portfolio withdrawals. Scheduled deposits and withdrawals occur on their entered timing and can materially change a solved age.
What the results mean
- Financial independence age
- The first whole age at which modeled accumulation reaches the required portfolio. Pension and part-time income reduce the monthly portfolio gap from the dates they arrive.
- FIRE number
- The smallest portfolio on the retirement boundary that can fund every modeled monthly net-spending gap and scheduled expense through the horizon. In percentage mode, the chosen rate also caps the inflation-adjusted draw set by the retirement portfolio.
- FIRE number in today's money
- The retirement-date requirement discounted by inflation to current purchasing power. The nominal FIRE number at a future age is larger because future dollars buy less.
- Portfolio at an age
- The modeled nominal balance at the stated milestone. Compare it with the FIRE number for that same date, not with a target quoted in today's dollars.
- The money lasts or depletion age
- The steady-return projection either finishes the end age with money remaining or identifies when the balance first can no longer fund the modeled withdrawal.
- Most you could spend
- The maximum modeled fixed spending, in today's money, that finishes the plan on zero at the end age. It is a mathematical ceiling with no buffer for worse outcomes, not a recommendation.
- Chance it lasts
- A simulated survival rate: 500 seeded runs vary monthly returns around the entered working and retirement rates using 15% annual volatility, while inflation and other assumptions stay fixed.
- Spendable in the first year
- The income available after modeled withdrawal tax and other income. Under a percentage rule it begins from the retirement-date portfolio; under fixed spending it follows the entered target.
Worked example
Four questions about one starting plan
Hypothetical example: at age 35, start with $150,000, contribute $24,000 a year, target $60,000 of annual retirement spending in today's money, and plan through age 95. Assume 7% while working, 5% in retirement, and 2% inflation. Spending rises with inflation; pension, withdrawal tax, and extra cash flows are off. The desired traditional retirement age is 65. For Barista FIRE only, include $30,000 a year of part-time income through age 65.
- Age 35Start with $150,000 and contribute $24,000 a year.
- Age 42Coast FIRE: regular contributions could stop, with growth continuing toward age 65.
- Age 55Barista FIRE: financial independence with $30,000 of part-time income through 65.
- Age 58FIRE: modeled financial independence without future salary or contributions.
- Age 65Traditional retirement: test the retirement age entered in the form.
- Age 95Plan end: every alternative must fund its cash flows through this age.
| Mode | Answer | What changes |
|---|---|---|
| Traditional retirement | Retire at 65; money lasts to 95 | After contributions continue through the working period, about $2,473,120 remains at 95 in today's purchasing power. |
| FIRE | Financial independence at 58 | The modeled portfolio is about $2,303,445 against about $2,153,373 needed on that date; salary and contributions then stop. |
| Coast FIRE | Stop saving at 42 | About $470,939 at 42 grows without regular contributions to about $2,232,503 at 65, versus about $2,184,145 needed. |
| Barista FIRE | Financial independence with part-time work at 55 | The portfolio is about $1,780,271; $30,000 of part-time income covers part of spending through 65. |
| 4% rule comparison | $1,500,000 FIRE number in today's money; FIRE at 59 | Four percent of $1.5 million supplies the $60,000 first-year target before inflation, so this rule reaches its target a year later than the fixed-spending result. |
The timeline places four alternative answers on one scale. It is not one recommended life sequence: for example, the FIRE answer assumes contributions continue to 58, while the Coast answer stops them at 42.
Assumptions and limitations
- The main projection uses steady returns. As GAO's retirement-income research illustrates, a poor sequence near or just after retirement can deplete a portfolio much faster than the same average returns arriving in a different order.
- The simulated survival result varies investment returns but holds inflation, spending behavior, taxes, income, and volatility fixed. It is not a forecast, stress test of every risk, or guarantee.
- Return, inflation, withdrawal rate, spending, pension, and part-time income are assumptions rather than forecasts or recommendations. Compare cautious and adverse scenarios.
- The classic percentage rule sets the first withdrawal from the retirement-date portfolio and then raises that dollar amount with inflation. Bengen's original historical analysis does not promise the same outcome for a different horizon, portfolio, fee level, tax situation, or future market.
- Under either spending style, pension, Social Security, and part-time income meet part of the desired net spending in the months they arrive. The portfolio withdrawal supplies the remaining gap and is grossed up when withdrawal tax is enabled.
- The model uses a flat tax only when enabled. It does not distinguish taxable, Roth, and tax-deferred accounts; enforce access ages or RMDs; model tax brackets; or optimize withdrawal order.
- Healthcare, long-term care, changing spending, insurance, partner finances, benefit claiming choices, and law changes need separate consideration. End age is a planning horizon, not a life-expectancy prediction.
Sources and further reading
Sources reviewed August 2026. These sources explain retirement concepts and research; they do not endorse this calculator, a FIRE strategy, or any withdrawal rate.
- U.S. Department of Labor: Taking the Mystery Out of Retirement Planning — a retirement-planning framework covering income needs, savings, inflation, investment returns, and longevity.
- U.S. Government Accountability Office: Retirement Income—Ensuring Income throughout Retirement Requires Difficult Choices — longevity, drawdown choices, and how the sequence of returns can change sustainability even when average returns match.
- William P. Bengen: Determining Withdrawal Rates Using Historical Data — the original historical analysis commonly associated with the 4% withdrawal rule.
- Social Security Administration: Get a benefits estimate — personalized benefit estimates based on an official earnings record and claiming age.