Retirement & FIRE Calculator
See whether you're on track to retire on your terms — with FIRE variants for early-retirement scenarios.
Build your plan
Pick a mode, enter your numbers, watch the math.
How this calculator works ↓New to a term? Money terms explained.
Your plan
Mode—
Where you'll land
Year-by-year savings
| Age | Contributed | Balance |
|---|
How this calculator works
The calculator projects your retirement savings forward one month at a time, then compares the result with the amount you would need to fund your retirement spending.
- Projected savings. Each month your balance grows by one twelfth of the annual return, then your monthly contribution is added. The contribution is your annual income times your savings rate, divided by 12, and it stays constant for the whole projection.
- Your number. Annual expenses in retirement multiplied by 1 ÷ withdrawal rate (the share of your savings you take out each year). At the default 4% withdrawal rate that is 25 times expenses: $60,000 a year needs $1.5 million.
- Required savings rate. The calculator solves the compound-growth (future-value) formula backwards to find the monthly contribution that lands exactly on your number by your target age, then expresses it as a percentage of income.
- Income replacement. Projected savings times the withdrawal rate, divided by your current income: the share of today's income your portfolio could supply.
The FIRE modes change the inputs, not the math. Lean, FIRE and Fat preset the spending level and, for Fat, a 3.5% withdrawal rate. Barista FIRE subtracts your expected part-time income from expenses before computing your number. Coast FIRE stops contributions at the coast age you set and lets the balance compound on its own until the target age.
The status line calls a plan "on track" when projected savings meet your number, "close" when they reach at least 80% of it, and "off track" below that.
Assumptions and where they come from
| Assumption | Default | Source / note |
|---|---|---|
| Default annual return | 7% | Roughly the long-run S&P 500 return after inflation. Before inflation (the nominal return) the index has returned about 10% a year over 1928–2025 (NYU Stern, Damodaran). Because the expenses you enter are in today's dollars, use an after-inflation return, not the nominal one. |
| Default withdrawal rate | 4% (25× expenses) | The "4% rule" from Bengen's 1994 study and the 1998 Trinity study, which found that 4% inflation-adjusted withdrawals from a stock-heavy portfolio lasted 30 years in most historical periods (summary and sources). Early retirees often use 3–3.5% for longer horizons. |
| Inflation | Not applied to contributions or expenses | Expenses are in today's dollars and the contribution never rises with raises. Using a real return keeps the projection roughly in today's dollars. |
| Taxes | Ignored | Growth is treated as untaxed and withdrawals as untaxed. Traditional 401(k) and IRA withdrawals are taxable; adjust expenses upward if most of your savings are pre-tax. |
| Social Security and pensions | Not included | Add expected benefits by lowering the expenses the portfolio must cover. |
| Fees and sequence of returns | Ignored | The return is applied evenly every month. Real markets deliver returns in lumps, and a bad first decade of retirement matters more than the average. |
| Mode presets | Lean $35k, FIRE $50k, Fat $100k at 3.5% | Conventions from the FIRE community, not rules. Every preset is editable. |
Assumptions last reviewed: September 2026.
Frequently asked questions
What is a FIRE number?
The amount of savings that lets your investments cover your spending indefinitely. The common shortcut is 25 times annual expenses, which is the same as a 4% withdrawal rate. Spending $50,000 a year gives a FIRE number of $1.25 million; at a 3.5% withdrawal rate it is about $1.43 million.
Is a 7% return realistic?
It is close to the long-run after-inflation return of the S&P 500, but it is an average over almost a century, not a promise for any particular decade. Ten-year stretches have delivered far less and far more. Try 5% and 9% to see the range.
What is the difference between coast FIRE and barista FIRE?
Coast FIRE means you have saved enough that, with no further contributions, compounding alone reaches your number by your target age; you only need to earn enough to cover current expenses. Barista FIRE means your portfolio covers part of your spending and part-time work covers the rest, so you can withdraw less than your full expenses.
Does the calculator include Social Security or a pension?
No. The simplest way to account for them is to reduce the annual expenses you enter by the benefit you expect, since the portfolio only needs to cover the rest.
Why does the required savings rate look so high?
Because your number is large relative to the time left. The formula solves for the contribution that hits the target exactly at your retirement age. Extending the target age by a few years or lowering planned expenses usually moves it the most.
Should I use my gross or net income?
Enter gross (pre-tax) income and think of the savings rate as the share of gross pay going into retirement accounts, including any employer match. If you prefer net income, keep the two consistent: net income with a net-of-tax savings rate.
This calculator is educational. It is not financial, tax, investment or legal advice. The assumptions are simplified; check them against your own situation or a licensed professional before acting on a result. See the Terms of Use.