FIRE Calculator — When Can You Retire Early?
The FIRE calculator shows when you can stop working and live off your investment portfolio returns. Enter your income, expenses, and expected return to see your FIRE number (target capital) and the age you will reach it. The tool accounts for inflation and checks whether your capital will last until your expected lifespan.
Updated:
Your current monthly spending — rent, food, transport, etc.
Historical avg. for diversified global ETF portfolio: ~7%
Polish avg. inflation 2010–2025: ~3.5%
How much you plan to spend per month after retiring. Usually lower than today — no commuting costs, no mortgage, etc.
Your FIRE Number
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The 4% rule — historically safe for 30+ year retirements
⚠️ At your current savings rate, you won't reach FIRE by age 80. Increase income or reduce expenses to make progress.
FIRE Number
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FIRE age
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Years to FIRE
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Portfolio at retirement
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Monthly retirement budget
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Lean FIRE (75% expenses)
Standard FIRE
Fat FIRE (150% expenses)
Progress to FIRE
0%
Portfolio growth over time
Example: when can you FIRE saving PLN 4,000 a month?
You are 30, with PLN 50,000 saved. You earn PLN 8,000 net and spend PLN 4,000 a month, so you save PLN 4,000 (50% of income). In retirement you want to spend PLN 3,000 a month in today's money. We assume a 7% annual return, 3.5% inflation and a 4% withdrawal rate.
| Variant | FIRE Number | FIRE age | Years to FIRE |
|---|---|---|---|
| Lean FIRE (75% expenses) | PLN 675,000 | 42 | 12 |
| Standard FIRE | PLN 900,000 | 46 | 16 |
| Fat FIRE (150% expenses) | PLN 1,350,000 | 53 | 23 |
Your FIRE number is PLN 900,000 (PLN 3,000 × 12 ÷ 4%). You reach it at age 46, in 16 years and 2 months.
These numbers come from the same calculator you see above, using its default inputs. Enter your own to see your result.
How we calculate
FIRE number = annual retirement spending ÷ withdrawal rate. With the 4% rule that is 25 times your annual spending. The target is in today's money and grows with inflation every month in the simulation.
Monthly savings are income minus current expenses. Each month the portfolio grows by the expected return (annual ÷ 12) plus your savings. You reach FIRE in the month the portfolio catches up with the inflation-adjusted FIRE number.
After retiring, we withdraw your inflation-adjusted retirement spending every month and check whether the money lasts until your life expectancy.
Assumptions: the same return every year (no crashes or sequence-of-returns risk), the same monthly savings in złoty (as if your pay never rose) while the target grows with inflation, results before Polish capital gains tax (19%) and fees, and no state pension (ZUS), which would lower the amount you need from the portfolio. If you save more as you earn more, you reach FIRE sooner.
Frequently Asked Questions
What is FIRE and financial independence?
FIRE (Financial Independence, Retire Early) is a lifestyle philosophy focused on aggressively saving and investing to retire much earlier than the traditional retirement age. Financial independence means having enough invested capital that the returns cover your living expenses without needing employment income. The FIRE movement is gaining popularity in Poland as an alternative to the conventional work-until-65 model.
What is the 4% rule and is it safe?
The 4% rule comes from William Bengen's 1994 analysis, popularised by the 1998 Trinity Study. It suggests you can safely withdraw 4% of your initial retirement portfolio annually (adjusted for inflation) without running out of money for at least 30 years. For shorter retirements, 4% is very conservative. For longer ones (45–50 years), many experts recommend 3.25–3.5%. This calculator defaults to 4%, but you can adjust it.
What is the difference between Lean FIRE, Standard FIRE, and Fat FIRE?
Lean FIRE means early retirement at minimal expenses — typically 75% of your current spending level. Standard FIRE maintains your current lifestyle. Fat FIRE is retirement at a higher standard — 150% of current expenses, providing more comfort and safety margin. The difference is how quickly you want to achieve independence and what standard of living you are willing to accept in retirement.
How much do I need to retire early in Poland?
It depends on your planned retirement expenses and chosen withdrawal rate. Using the 4% rule: FIRE Number = monthly retirement expenses × 12 ÷ 0.04. For example, with 3,000 PLN monthly retirement expenses you need about 900k PLN. With 2,250 PLN (Lean FIRE) — 675k PLN, and with 4,500 PLN (Fat FIRE) — 1.35 million PLN. The key factor is how much you can save and invest regularly each month, and how much you can reduce expenses after retiring.
What investment return rate should I assume for FIRE calculations?
For a diversified global portfolio (e.g., world ETF), the historical average annual return is about 7% nominally. After subtracting inflation (~3.5%), this gives roughly 3.5% real return. Many FIRE planners use 5–7% nominal returns in their calculations. It is important not to be overly optimistic — it is better to be conservative in planning and pleasantly surprised than to assume unrealistic return rates.
Guides
The 4% rule — how much do you need for FIRE?
The 4% rule tells you how much capital lets you live off your investments. Where it comes from, what it assumes, how to adapt it for Poland and how long it takes.
Compound interest — how it works and why time matters
Compound interest in practice: the formula, examples over 10, 20 and 30 years, the rule of 72 and the effect of fees, the Belka tax and inflation.
Other calculators
IKE, IKZE or PPK?
IKE, IKZE or an ordinary account: which leaves you more for retirement? With the IKZE tax refund, the limits and a PPK comparison.
Compound Interest Calculator
See how your savings grow with regular contributions — after inflation and Polish capital gains tax.
Polish inflation calculator
What is money from years ago worth today? Work out inflation in Poland between any two months since 1991, using up-to-date GUS data.