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FIRE calculator

Financial independence means your investments pay for your life, so work becomes optional. Find the portfolio that would cover your spending, and how long your savings take to get there.

By Michael Afreh, senior software engineer with 12+ years in e-commerce, fintech and banking, and author of The Software Engineer's Guide to Investing. Reviewed 31 October 2026.

1 · Where you are
years

Used to show the age you could stop working.

Investments meant for retirement, not your emergency fund.

What you invest every month.

2 · The life you want

In today's money, including health insurance.

%

Share of the portfolio you take out in the first year. 3–4% is common.

%

Effective rate on what you sell. At most 18.46% for a German equity ETF; see the FAQ.

3 · Returns
%

Yearly return after inflation and fees.

± %

Shows how a weaker or stronger market moves the date.

Your FIRE number

1,028,571

At 5%, you could reach it in 22 years, at age 54.

Monthly spending covered
3,000
At 7% return
19 years
At 3% return
26 years
  • Balance at 5%
  • Range 3% – 7%
  • Total paid in
  • FIRE number
01M2M3M4MYr 0Yr 5Yr 10Yr 15Yr 20Yr 25Yr 30FIRE number 1M
Year-by-year table
YearPaid inInterestBalanceLow – high
050,000050,00050,000 – 50,000
174,0003,04577,04575,828 – 78,261
298,0007,443105,443102,431 – 108,499
3122,00013,260135,260129,833 – 140,855
4146,00020,568166,568158,056 – 175,475
5170,00029,442199,442187,126 – 212,519
6194,00039,959233,959217,068 – 252,156
7218,00052,202270,202247,908 – 294,568
8242,00066,257308,257279,673 – 339,948
9266,00082,215348,215312,392 – 388,505
10290,000100,171390,171346,092 – 440,461
11314,000120,225434,225380,803 – 496,054
12338,000142,481480,481416,555 – 555,538
13362,000167,050529,050453,380 – 619,187
14386,000194,048580,048491,310 – 687,290
15410,000223,596633,596530,377 – 760,161
16434,000255,821689,821570,617 – 838,133
17458,000290,857748,857612,063 – 921,563
18482,000328,845810,845654,754 – 1,010,833
19506,000369,932875,932698,724 – 1,106,352
20530,000414,274944,274744,014 – 1,208,557
21554,000462,0331,016,033790,663 – 1,317,917
22578,000513,3791,091,379838,711 – 1,434,931
23602,000568,4941,170,494888,201 – 1,560,137
24626,000627,5631,253,563939,175 – 1,694,107
25650,000690,7871,340,787991,679 – 1,837,455
26674,000758,3711,432,3711,045,757 – 1,990,838
27698,000830,5351,528,5351,101,458 – 2,154,957
28722,000907,5071,629,5071,158,830 – 2,330,565
29746,000989,5271,735,5271,217,923 – 2,518,465
30770,0001,076,8491,846,8491,278,789 – 2,719,518
31794,0001,169,7371,963,7371,341,481 – 2,934,645
32818,0001,268,4692,086,4691,406,054 – 3,164,831

What the FIRE number is

FIRE stands for financial independence, retire early. Your FIRE number is the portfolio large enough that you can take out your yearly spending and, historically, not run out. It is your spending divided by your withdrawal rate: 36,000 a year at 4% needs 900,000; at 3.5% it needs about 1,029,000.

Where the 4% rule comes from

In 1994, financial planner William Bengen tested withdrawals against U.S. stock and bond returns since 1926. Taking 4% of the portfolio in the first year, then raising the amount with inflation, lasted at least 30 years in every period he tested. The 1998 “Trinity study” reached a similar result. Both looked at 30-year retirements; if you stop at 40, yours could last 50 years, which is why many early retirees plan with 3–3.5%.

Why everything is in today's money

The calculator uses a real return, meaning after inflation. That keeps every number in today's purchasing power: a FIRE number of 900,000 means a portfolio that buys what 900,000 buys now. If stocks return 7% and inflation runs at 2%, enter about 5%.

If you live in Germany

Two things change the plan. Once you stop working, you pay health insurance yourself, so include it in your spending. And the statutory pension starts at 67 for anyone born in 1964 or later, so from then on your portfolio only has to cover the gap. Your yearly Renteninformation from the Deutsche Rentenversicherung shows the pension you have earned so far.

Frequently asked questions

+Which withdrawal rate should I use?

4% is the classic figure for a 30-year retirement. For 40 years or more, 3–3.5% leaves more room for a bad decade at the start, which is the biggest risk to an early retirement. Being willing to spend less after a crash helps as much as a lower rate.

+How do I estimate the tax on withdrawals?

In Germany (2026 tax year), investment income above the saver's allowance of 1,000 € a year (2,000 € for married couples filing jointly) is taxed at a flat 25% plus the 5.5% solidarity surcharge on that tax, 26.375% in total, plus church tax if you pay it. For equity ETFs, 30% of the gain is tax-free, which brings the effective rate on gains to about 18.46%.

Only the gain part of what you sell is taxed. If half of your portfolio is gains, an equity ETF withdrawal costs about half of 18.46%, around 9%, before the allowance. The share of gains grows the longer you hold.

+Should I count my state pension?

This calculator leaves it out, which is the cautious choice. If your pension will cover part of your spending later, you need a smaller portfolio after that age, but you still need enough to bridge the years before it starts.

+What return should I expect?

Nobody knows. Global stocks have returned roughly 5% a year after inflation over long periods, with decades well above and below that. A mix with bonds returns less but swings less. Use the variance to see how sensitive your date is.

+What are lean FIRE and coast FIRE?

Lean FIRE plans for a frugal budget, so the number is smaller. Coast FIRE means you have invested enough that, with no more saving, growth alone reaches your number by a normal retirement age; you then only need to earn your current spending.

chaos engineering

Break it on purpose

A FIRE number is a single point estimate. The Software Engineer's Guide to Investing shows how to drill the plan against a 40% drawdown or a year without income, so you find the weak spots before you hand in your notice.

Get the book on Amazon

Or read chapter one first, free:

One email with the chapter. No sequence, no drip campaign.

Sources

Not financial advice. The results are estimates for education, not a recommendation or a promise of returns. See the disclaimer.