Every flavor of the FIRE movement in one place: the classic FIRE number, the coast FIRE point where you can stop saving, and the Barista FIRE bridge into semi-retirement. Free, instant, no signup, all math runs in your browser.
FIRE stands for Financial Independence, Retire Early. The core idea: save and invest a high share of your income, often 30–50% or more, until your portfolio can fund your living expenses indefinitely. At that point paid work becomes optional: you can retire decades before the traditional age, or simply work on your own terms. The movement grew out of Vicki Robin and Joe Dominguez's 1992 book Your Money or Your Life and spread online in the 2010s through blogs like Mr. Money Mustache.
The default yardstick is the 4% rule: withdraw 4% of your portfolio in the first year of retirement, then adjust that dollar amount for inflation each year, and historically the money lasted at least 30 years. It comes from William Bengen's 1994 paper Determining Withdrawal Rates Using Historical Data and was stress-tested by the 1998 Trinity Study (professors Cooley, Hubbard and Walz of Trinity University) against every US start year since 1926. Flip it around and you get the classic FIRE formula: you need roughly 25× your annual spending. The rule is a planning convention, not a guarantee, it assumes a stock-heavy portfolio, and people retiring very early often choose 3.25–3.5% for longer horizons. Every calculator here lets you set your own rate.
| Variant | Idea | Trade-off |
|---|---|---|
| Lean FIRE | Retire on a stripped-down budget | Smallest number, least slack for surprises |
| FIRE (regular) | 25× your normal annual spending | The classic benchmark |
| Fat FIRE | Retire with a cushier budget, more travel, more buffer | Largest number, takes longest |
| Coast FIRE | Your current investments are already enough; growth alone finishes the job, so you stop saving and just cover today's bills | Still need income for current spending |
| Barista FIRE | Semi-retire: the portfolio covers part of your spending and a low-stress part-time job covers the rest | Depends on part-time income staying available |
"How much do I need in total?" → FIRE Number Calculator, also shows lean and fat variants and your estimated FIRE date.
"When can I stop saving for retirement?" → Coast FIRE Calculator, also searched as the coastfire calculator.
"What if I keep some part-time income?" → Barista FIRE Calculator, see how much smaller the target gets.
All three calculators work in today's dollars: returns are real (after-inflation) returns with a default of 6% per year, roughly the long-run historical real return of US equities (Dimson, Marsh & Staunton, Credit Suisse Global Investment Returns Yearbook), and withdrawal rates default to 4%. Taxes, investment fees and sequence-of-returns risk are not modeled, so treat the outputs as planning estimates and stress-test them with lower returns and higher spending. All math runs locally in your browser; the numbers you type never leave your device.