FIRE Calculator
Enter what you have saved, what you invest, your expected return, inflation and what you need each month to live. You will see how many years you have left, the date and the age you would get there.
Enter your savings or a contribution, the return, inflation and your monthly spending.
Estimate with constant returns and inflation, before taxes and fees. Your contribution rises with inflation every year, just like the target.
Year by year
Enter your savings or a contribution, the return, inflation and your monthly spending.
Results are estimates. Solvemis accepts no responsibility for the results obtained or for how they are used. Always double-check the result and talk to a qualified professional before making decisions.
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How it works
How to use it
- Enter what you already have invested and how much you contribute, and choose monthly or yearly.
- Enter the annual return you expect, after fees, and average inflation. The Federal Reserve targets 2%.
- Enter what you need each month to live, in today's dollars.
- Choose the withdrawal rate: 4% is the classic rule; for a long early retirement, 3% to 3.5% is safer.
- To see the age you would get there, enter your age. Open the table for a year-by-year breakdown.
How it is calculated
Your FIRE number is your annual spending divided by the withdrawal rate. The calculator runs month by month: your portfolio grows at the monthly rate equivalent to the annual return, (1 + r)^(1/12) − 1, and receives your contributions. With inflation, the target grows every month and your contribution is raised once a year. You reach financial independence in the first month your portfolio reaches the target for that month.
FIRE number = annual spending ÷ withdrawal rate (at 4%: 25 × annual spending)
Sources
- Determining Withdrawal Rates Using Historical Data (William P. Bengen, 1994) — Journal of Financial Planning, Financial Planning Association
- Why does the Federal Reserve aim for inflation of 2 percent over the longer run? — Board of Governors of the Federal Reserve System
About this calculator
What financial independence means
You are financially independent when what your investments can pay out covers your expenses, and working becomes a choice rather than a necessity. That is the idea behind FIRE (Financial Independence, Retire Early): save and invest enough to be able to stop working before the usual retirement age.
The question is how much is “enough”. That is what the 4% rule answers.
The 4% rule
In 1994, financial planner William Bengen looked at what would have happened since 1926 to a retiree who withdrew a fixed percentage of their portfolio and raised it with inflation every year. At 4%, the money lasted at least 30 years in every case, even for people who retired right before the worst downturns. In 1998, the so-called Trinity study reached a similar conclusion.
That gives the math: your FIRE number is 25 times your annual spending.
| Withdrawal rate | Multiply annual spending by | At $4,000 a month |
|---|---|---|
| 4% | 25 | $1,200,000 |
| 3.5% | 28.6 | $1,371,429 |
| 3% | 33.3 | $1,600,000 |
| 2% | 50 | $2,400,000 |
| 1% | 100 | $4,800,000 |
The 4% rule was tested on retirements of about 30 years, using U.S. stock and bond returns. If you retire young, your money has to last longer, which is why the calculator lets you lower it.
An example
With $20,000 saved, $1,500 a month invested, a 7% return, 2.5% inflation and $4,000 a month in spending:
- Ignoring inflation: 24 years and 3 months.
- With inflation: 30 years and 8 months. By then the target is no longer $1.2 million but $2,558,860, which will buy what $1.2 million buys today.
If you start at 35, you would get there at 65. At a 3% withdrawal rate instead of 4%, it would take 35 years and 10 months.
Inflation counts twice
Inflation raises the target: what costs $4,000 today will cost more every year. That is why your contribution also has to rise with inflation every year to reach these results. If you keep investing the same amount, you are really saving a little less each year, and it will take longer.
The return you enter is the one you expect in each year’s dollars. What really grows your purchasing power is the gap between your return and inflation.
Social Security comes on top
If you expect Social Security or a pension, that is extra income. You can subtract it from your monthly spending and your target goes down: with $1,500 in benefits, you would need $2,500 a month, a $750,000 target, and you would get there in 23 years and 1 month. Remember that benefits start at 62 at the earliest, and are reduced if you claim before your full retirement age: if you stop working sooner, your savings have to cover all your spending until then.
What the result does not include
- Taxes and fees: enter your return after fees. Withdrawals from traditional 401(k)s and IRAs are taxed as income, and taxable accounts pay capital gains tax.
- Changing returns: the calculator assumes a constant return. Stock returns change every year and can be negative, and the order of bad years matters a lot once you start withdrawing.
- Life changes: spending, income and family change over the years.
All figures are estimates, not a forecast or financial advice. For a plan tailored to you, talk to a qualified professional. Solvemis accepts no responsibility for the results or for how they are used.
Frequently asked questions
What is the 4% rule?
If you withdraw 4% of your starting portfolio in the first year and raise that amount with inflation every year after, your money lasted at least 30 years in every historical period studied in the U.S. That gives your FIRE number: 25 times your annual spending. At $4,000 a month, $48,000 a year, that is $1.2 million.
Why lower it to 3%, 2% or 1%?
Because the 4% rule was tested on retirements of about 30 years. If you stop working at 40, your money may need to last 50 years or more, and a safer withdrawal rate is 3% to 3.5%. At 2% or 1% your portfolio barely gets touched and is mostly left to your heirs.
Why does inflation push the date back?
Because the $4,000 you need today will be a lot more in 30 years. With 2.5% inflation, a $1.2 million target today becomes more than $2.5 million by the time you reach it. The calculator shows both dates, with and without inflation, so you can see the difference.
What about Social Security?
Social Security is extra income on top of your portfolio. If you like, subtract the benefit you expect from your monthly spending and your target goes down. Keep in mind that benefits start at 62 at the earliest: if you stop working sooner, your savings have to cover all your spending until then.
Updated October 2, 2026
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