FIRE stands for Financial Independence, Retire Early. The idea is simple: save and invest aggressively until your portfolio can cover living expenses, then work becomes optional.
People reach FIRE at different speeds and lifestyles. Some quit work entirely; others switch to part-time or passion projects. The common thread is that money stops being the main reason to show up every day.
Your FI number
Your FI (financial independence) number is how much you need invested so withdrawals can fund your spending. A common shortcut is 25× annual expenses, based on the 4% safe withdrawal rate.
If you plan to spend $40,000 per year in retirement, a rough FI target is about $1,000,000. Lower spending means a smaller target; a more conservative withdrawal rate means a larger one.
Lean, Coast, and Barista FIRE
Lean FIRE targets a frugal lifestyle with lower annual spending. Coast FIRE means saving enough early that compound growth can carry you to traditional retirement without more contributions. Barista FIRE assumes part-time work covers part of your bills so you need a smaller portfolio.
Each path changes how much you need today and how soon you can leave full-time work. A comparison calculator helps you see the tradeoffs side by side.
Run your numbers
Articles explain the concepts; calculators turn your actual income, savings, and spending into a timeline. Start with your current age, portfolio, savings rate, and expected return, then adjust assumptions to see how sensitive your FIRE date is.