FIRE Calculator

What is the FIRE calculator – financial independence?

The FIRE calculator (Financial Independence, Retire Early) calculates how much investment wealth you need to retire early using the 4 percent withdrawal rule. The calculator also shows how long saving will take.

The calculator is free, works in your browser without registration, and provides results immediately. All figures are based on standard formulas; always check the rules that apply where you live.

Calculation formula

FIRE number = Annual expenses × 25 (4% rule). Time = ln((FV+PMT/r)/(PV+PMT/r)) ÷ ln(1+r)

Enter your values in the calculator fields and press the Calculate button – the result updates instantly. You can try different values to see how changes affect the outcome.

Practical example

Annual expenses $30,000/year → FIRE number $750,000. Initial capital $50,000, savings $2,000/month, return 7% → achieved in 14 years 3 months.

This example illustrates a typical situation. Enter your own numbers into the calculator to get a personal result.

Who is the calculator for?

The calculator serves employees, entrepreneurs, students, and anyone who wants a clear answer without complicated formulas. All calculators on this site are free and no registration is required.

You can always find accurate official information through your local tax authority or employer. This calculator provides a good estimate, but official decisions are made based on calculations by authorities.

Tips and considerations

• Calculate a realistic “lean FIRE” (minimum budget) and “fat FIRE” (comfortable budget) – the truth is likely somewhere in between.
• Consider inflation: over a 30-year horizon, 2% inflation significantly erodes purchasing power.
• A hybrid strategy (part-time work + investment income) is the most practical route to FIRE for many.