Early Retirement (FIRE) Calculator
From current savings and monthly contributions, work out the years and months to reach your target retirement fund.
Input Data
Results
At a glance:FIRE (Financial Independence, Retire Early) means accumulating enough assets so passive income covers daily expenses, letting you leave the workforce before the usual retirement age. The most common estimate is the '4% safe withdrawal rate rule': required retirement principal = annual expenses ÷ 4% = annual expenses × 25. That is, you withdraw only about 4% of the principal each year and let the rest grow with returns, so the assets are not depleted over the long run.
Formula
Monthly rate = annual return ÷ 12.
Month by month (end-of-period): new balance = previous balance × (1 + monthly rate) + monthly contribution.
Repeat until the balance reaches the target; tally the years and months required.
$$\\text{FIRE Number} = \\dfrac{\\text{AnnualExpenses}}{\\text{SWR}} = \\text{AnnualExpenses} \\times 25 \\quad (\\text{SWR} = 4\\%)$$$$n = \\dfrac{\\ln\\!\\left(\\dfrac{\\text{FV} \\cdot i + C}{P \\cdot i + C}\\right)}{\\ln(1+i)}$$How to Use
- First estimate your FIRE Number (target fund) as annual expenses × 25.
- Enter your current investable savings, monthly contribution and expected annual return.
- View the years and months to target, the balance at target and total contributions.
FAQ
Does the 4% withdrawal rule apply in Hong Kong?
The 4% rule comes from US historical data assuming a diversified equity portfolio can grow long term. Hong Kong has high living costs, private healthcare and property prices, and retirements can last over 30 years, so many adopt a more conservative 3%–3.5% withdrawal rate (principal × 28 to × 33) for a bigger safety margin against inflation and market swings. Treat it as an estimate and adjust to your own asset mix, spending and risk tolerance.
Hong Kong is expensive — how much do I need for a FIRE target?
It hinges on your annual expenses. At the 4% rule: annual spending of HK$300k needs about HK$7.5M, HK$480k needs about HK$12M, HK$600k needs about HK$15M. Rent and mortgage are usually the biggest items; if you own your home outright, your expenses and required principal drop sharply. Work out your real monthly spending first, then multiply by 25.
How does the MPF (locked until 65) affect early retirement?
Per the MPFA, MPF is generally withdrawable only at 65. Early withdrawal before 65 is limited to specific cases: aged 60 and permanently leaving employment, permanently leaving Hong Kong, total loss of capacity, terminal illness, small balance (≤ HK$5,000) or death. So if you plan to retire before 65, prepare separately accessible assets (savings and investments) to cover living costs until MPF becomes available — do not count MPF as immediately usable FIRE capital.
How does inflation erode my FIRE target?
Inflation raises future expenses and lowers purchasing power. HK$480k of annual spending today at 3% inflation needs about HK$860k in 20 years to keep the same lifestyle, and the FIRE Number rises accordingly. Counter it with a more conservative withdrawal rate (e.g. 3%), plan on the real return (nominal minus inflation), hold growth assets, and review expenses and assets regularly.
What is the basis of FIRE Number = annual expenses × 25?
It comes from the 4% safe withdrawal rate: if you withdraw only 4% of principal each year, required principal = annual expenses ÷ 4% = annual expenses × 25. The time-to-target in this calculator uses the standard annuity future-value (monthly end-of-period contribution) compounding model: each month's balance = previous balance × (1 + monthly rate) + monthly contribution, repeated until the target. Results are estimates only — no inflation, tax or volatility — and professional advice is recommended for real planning.
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References
Content review: Calculatorism Finance Team. Results are for reference only; please refer to the relevant authorities for the official figures.