FIRE (Financial Independence, Retire Early)

FIRE is the strategy of saving an extreme share of income — often 40–70% — to build a portfolio large enough that work becomes optional. The arithmetic is unforgiving and elegant: your time to independence depends almost entirely on your savings rate, not your salary. Save 10% and you need roughly 50 years; save 50% and it's about 17. The usual target is 25× annual spending, which pairs with a 4% withdrawal rate. Variants include lean FIRE (frugal), fat FIRE (comfortable) and coast FIRE (stop contributing, let compounding finish).