Lean FIRE Calculator

About this calculator

Lean FIRE is the minimalist branch of the FIRE (Financial Independence, Retire Early) movement, targeting a smaller nest egg built around a frugal, tightly budgeted annual spending level rather than a comfortable or lavish lifestyle. Like other FIRE variants, the target portfolio is calculated by dividing desired annual spending by a chosen withdrawal rate (commonly modeled around the 4% rule), so keeping planned expenses low is what makes the Lean FIRE number achievable sooner than FatFIRE or standard FIRE targets.

People pursuing Lean FIRE typically prioritize reaching financial independence as fast as possible over maintaining a higher standard of living, often planning around a minimal but sustainable budget, geographic arbitrage (living somewhere with a lower cost of living), or a willingness to pick up part-time or freelance income (sometimes called Barista FIRE) rather than relying purely on portfolio withdrawals.

This calculator takes your desired lean annual spending and withdrawal rate and returns the portfolio size needed to sustain it.