FIRE / Retirement Number Calculator

FIRE Calculator works out the two numbers at the centre of the financial independence movement: the portfolio size that covers your spending forever, and how long it takes to get there. The FIRE number is annual expenses divided by your safe withdrawal rate — at the traditional 4% rule that means 25 times annual spending, though the rate is adjustable because the debate over whether 4% is still right has never settled. From your current net worth and annual savings, the tool projects forward year by year at your expected return until the portfolio reaches the target, reporting the number of years, your savings rate, and current passive income at your withdrawal rate. Lean and Fat FIRE targets are shown alongside the standard one, and a progress bar makes your position visible. All maths is currency-agnostic, so it works identically in any country.

Key Features

• Adjustable Withdrawal Rate

  Defaults to 4% but fully editable, since 3% and 3.5% are increasingly common assumptions for longer retirements.

• Years to Independence

  Projects year by year rather than using a closed-form formula, so the result reflects compounding on a growing balance.

• Lean, Standard and Fat FIRE

  Three targets at 75%, 100% and 150% of your expense level, covering the common variants of the goal.

• Savings Rate Calculation

  Derives your savings rate from savings and expenses, since savings rate predicts time to FI better than income does.

• Current Passive Income

  Shows what your existing portfolio would safely produce today, which is often more motivating than the distant target.

• Currency-Agnostic

  No tax tables or country assumptions — pure arithmetic that works with any currency and any jurisdiction.

1. 1

   Enter your net worth

   Count invested assets you would actually draw on. Excluding your primary home is the usual convention.

2. 2

   Enter annual expenses

   Your real annual spending, since this sets the target directly. Understating it is the most common error.

3. 3

   Enter annual savings

   What you invest each year. Combined with expenses this gives your savings rate.

4. 4

   Set the expected return

   Use a real return after inflation if your expenses are in today’s money, which keeps the comparison consistent.

5. 5

   Set the withdrawal rate

   4% is traditional; 3% to 3.5% is more conservative for early retirees with long horizons.

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