Estimate your FIRE number, projected retirement timeline, and portfolio longevity — based on your own numbers and the 4% Rule. One purchase gets you both: the web app and the same calculator as an Excel file you keep.
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Sample result — Age 32, $55K saved, $60K income
Tap ƒ to see the formula.
📊Also included: the Excel workbook — the same inputs and these results, plus Goal Mode, Life Events and Monte Carlo, all as live formulas. Change a blue cell and everything recalculates.
…and more: portfolio charts, the retirement drawdown table, Goal Mode options for changing your income or several inputs, plus a built-in "How it works" guide.
Tap a picture to see it full size.
Based on the 4% Rule · Trinity Study (1998). All of this is in both the web app and the Excel workbook.
Estimate how much you need to retire — based on your withdrawal rate and retirement expenses.
See how your portfolio grows each year until it hits your FIRE number — as a chart and as a full year-by-year table.
Find out if you can stop saving now and let compound interest do the rest.
Set a goal retirement age and see exactly what needs to change to get there.
Add salary raises, career breaks, or big expenses and see how your FIRE timeline shifts.
Run 1,000 random scenarios to see the probability your portfolio survives 40 years.
Adjust each input to your own situation — your age, savings, withdrawal rate and life events — and see how each scenario plays out. The same inputs are already laid out in both versions — nothing to set up.
Both versions start with typical values already filled in — type over any of them, and check how each result is worked out.
Age, savings, income, expenses, investment returns, withdrawal rate — type over any starting value to match your own plan.
Tap ƒ next to a result, a table column or a chart line to see how it's calculated, step by step.
Paste your inputs, results and the full year-by-year table into Excel or Google Sheets — change any input there and everything recalculates.
Type any number you like — values are used exactly as you type them, and every number in the workbook updates.
Every result is a live formula — click any result cell and the formula shows in the formula bar.
Change or extend any formula. The "How it works" sheet explains each part and the assumptions behind it.
Buy once and use both versions as often as you like — run every scenario you need.
Open your link in any browser and start right away.
Install once on your phone or computer, then use it anywhere — even with no internet.
Keep each scenario separately — 3.5% vs 4% withdrawal, retire at 45 vs 50.
Desktop & AndroidSend a scenario to your partner or advisor.
The .xlsx is yours to keep — open it any time, no internet needed.
Save a copy for each plan — 3.5% vs 4% withdrawal, retire at 45 vs 50 — and compare them side by side.
Microsoft Excel, Google Sheets or LibreOffice.
🔒 No account, no subscription — your data stays on your device.
Enter your numbers and see your FIRE plan in a clear, easy-to-understand format.
🔒 Secure checkout via Gumroad · Card or PayPal · Instant download
Need more than one? Get all 5 calculators for $39.99 →