Retirement & FIRE calculator
One retirement model can answer four related questions: when your portfolio could support you, when you could stop contributing, and whether the money lasts through the planning period.
What should be calculated
Advanced options
Extra deposits
Money arriving outside the contribution — a bonus, a stock grant. With no limit it continues through the whole plan; use the time-range choice to confine it before retirement, after retirement, or to named years.
Extra withdrawals
Scheduled withdrawals for expenses such as a vehicle, roof replacement, or tuition. Either a sum or a share of the portfolio, working or retired.
Scenario comparison
Retirement timeline
Saving, retirement, outside-income phases, and key modeled moments across the full plan.
RMD eligibility is age-only context. Account type, plan and employment exceptions, distribution amounts, and tax are not modeled.
Retirement readiness
Portfolio balance by age
Retirement cash flow
Sequence-risk range
First shortfall age
Shortfall severity
Annual contribution increase
For the scenario selected above, the extra annual contribution needed on top of what you already put in to retire at each age.
Required withdrawal rate
What the rule pays
Return sensitivity
How the portfolio changes when either assumed return differs from the figure entered.
The portfolio on the day you retire, at each return while working. The banded column is your return.
What is left at the end age, at each return while retired — zero if the portfolio is depleted before the selected end age.
Annual projection
| Age | Added | Growth | Taken out | Part-time | Portfolio | Today’s $ |
|---|
Portfolio in today’s money
Cash-flow schedule
Every extra event the monthly projection will execute through the end age. Repeating entries continue through retirement unless their own time range limits them.
| Year + month | Value | Deposit type |
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What this model assumes
- The return is the same every year. For a retirement plan, this assumption can obscure the effect of variable returns. Losses early in retirement can reduce the portfolio’s ability to fund later withdrawals, even when average returns match the assumption.
- The one figure that does not assume a steady return is the chance the spending target is fully funded: five hundred runs of the same plan with the return drawn afresh each month, at a 15% yearly standard deviation. A run fails when any modeled spending target or scheduled withdrawal is not paid in full; that is different from saying a still-positive portfolio has reached zero.
- Max spending is the largest fixed sum, in today’s money, that the settled monthly plan can pay in every retirement month. A later deposit cannot make an earlier unpaid month count as funded.
- Every amount is entered in today’s money. Contributions and any part-time income rise with inflation from here, and retirement spending does too unless you switch that off. Each extra scheduled deposit or withdrawal has its own inflation switch, off by default. Money is taken out at the start of each month and the balance grows on what is left.
- An extra deposit lands on the last month of each of its own periods and, with no time-range limit, continues through the whole plan, including retirement. A before-retirement, after-retirement, or explicit year range limit narrows it.
- The percentage rule sets a maximum first-year gross portfolio draw from the balance on the day you retire, with that cap raised by inflation. The state machine draws only the net spending gap left after outside income. The FIRE number is the smallest retirement-day portfolio that can meet those monthly gaps within the rule cap and last through the selected horizon.
- A pension or Social Security and tax are both off until switched on. Outside income reduces the monthly spending gap in both modes, including in the solved FIRE number and age. Tax is a flat rate on every dollar drawn from the portfolio, including scheduled withdrawals, but not on outside income; no brackets or account types are modeled.
- Not modelled: account types and their withdrawal rules, healthcare before pension age, changes in volatility or inflation over time, or a partner with a plan of their own. These projections are informational estimates, not personalized retirement advice. Actual outcomes depend on the timing and variability of returns.
Calculations are estimates based on your assumptions and are not financial or investment advice. Actual results may differ. Read the financial disclaimer.