About FIRE Engine
FIRE Engine is a free calculator built to make one of the most important numbers in personal finance easy to see: the age you could reach financial independence and retire early.
What we do
We turn a handful of inputs — your net worth, income, expenses, expected return, and withdrawal rate — into a clear projection: your FIRE number, your savings rate, and a year-by-year chart of your net worth compounding toward the finish line. No spreadsheets, no sign-up, no jargon. Alongside the main calculator we cover the major variants of the movement — Lean FIRE, Fat FIRE, Coast FIRE, and Barista FIRE — each with its own tailored calculator.
Why it's private
The calculator runs entirely in your browser. The financial details you enter never leave your device and are never sent to a server. We believe a tool that handles sensitive money questions should respect your privacy by default. See our Privacy Policy for the full details.
A note on accuracy
Our projections are intentionally simple and transparent so you can understand every assumption. They do not replace personalized advice from a qualified financial professional, and real-world results are affected by taxes, inflation, fees, and market timing. Use FIRE Engine as a starting point for planning and conversation, not as a guarantee. Full details are in our Terms of Use.
Who we are
FIRE Engine is an independent project run by a small team that follows the FIRE movement personally. We built the tool we wanted ourselves: fast, private, and free of the sign-up walls and data harvesting common to financial sites. The site is supported by advertising so it can stay free to use.
Questions, corrections, or partnership ideas? Head to our Contact page.