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Fire Calculator
If you've landed here looking for fire calculator, you probably want a working tool, not a wall of text. Here's the free Fire Calculator that handles it, plus what to watch out for.
Open the tool
Safe withdrawal rate inputs; inflation assumptions; savings rate.
Open the Fire Calculator →🚀 Quick-Start Guide
Log your first entry above. Add more entries as they happen. Watch your running total and average update automatically.
Common Scenarios & Troubleshooting
Add specific toggle states for "LeanFIRE"; "FatFIRE"; and "CoastFIRE" targeting.
Note on errors: the most common slip-up here is rounding the wrong number, or forgetting a recurring cost that quietly changes the real total. If that happens, double-check your input rather than the tool — the calculation itself runs the same way every time.
Your data stays private. Everything you type runs locally in your own browser tab. Nothing is uploaded, logged, or stored on a server — close the tab and it's gone.
Behind the Scenes: The Processing Logic
This tool processes everything client-side, inside your browser window, using a simple running array held in memory for the length of your session. Complex mathematical modeling compressed into lightweight client JS Nothing is sent to a server, so there's no upload delay and no privacy trade-off.