About this calculator

FIRE Calculator is a free, fast tool for estimating your path to Financial Independence / Retire Early (FIRE). It runs entirely in your browser — we don't collect or store the numbers you enter.

Who's behind FIRE Calculator

FIRE Calculator is built and maintained by the FIRE Calculator editorial team — an independent group focused on financial independence and early-retirement planning. We're not a bank, broker, or advisor; we build free, transparent tools and explain the math behind them so you can check it yourself.

Why we built FIRE Calculator

Financial independence shouldn't be a black box reserved for people who love spreadsheets. We built FIRE Calculator to make the math simple and honest: put in real numbers, see a clear path to the day work becomes optional, and understand every assumption behind the result. Whether you're aiming for Lean, Coast, Barista, or Fat FIRE, the goal is the same — replace vague hope with a number you can actually plan around. New to the idea? Start with What is FIRE?

The methodology

The tool uses standard, public-domain personal-finance math:

• FIRE number = target annual spending ÷ safe withdrawal rate (SWR). At a 4% SWR this is the "Rule of 25" (spending × 25).
• Projection: each year we grow your investments by a real rate of return (return minus inflation) and add your savings, until the balance reaches your FIRE number — giving your years to FI and FIRE age.
• Coast FIRE = target ÷ (1 + real return)^(years to traditional retirement) — the amount you'd need invested today to reach your number with no further saving.
• Barista FIRE: optional part-time income lowers the spending your portfolio must cover.
• FIRE type (Lean / Standard / Fat) is detected from your spending level; Days of freedom shows how many days a year your current portfolio already covers at your SWR.
• Longevity context = how long your savings may need to last, based on the average life expectancy of your selected country (World Bank, life expectancy at birth, 2024). About half of people live longer than average, so planning to age 90+ adds a safety margin.

All figures are shown in today's dollars (inflation-adjusted) by default.

Data sources

Life-expectancy by country: World Bank Open Data (life expectancy at birth, 2024). The 4% safe withdrawal rate originates from research by William Bengen (1994) and was reinforced by the Trinity Study (Cooley, Hubbard & Walz, 1998) — both public-domain findings widely cited in personal finance. Return/inflation assumptions reflect common long-run averages and are fully editable.

Important

This is an educational tool, not financial advice. Real outcomes depend on market sequence-of-returns, taxes, healthcare and life changes the model simplifies. Consult a qualified professional before making decisions.

How we keep it free

FIRE Calculator is free. Some links to third-party tools are partner links — if you sign up through one, we may earn a commission at no extra cost to you. It never changes our math or which tools we mention.

Contact

Questions, feedback or a correction? Send us a message and we'll get back to you.