Three flavors of FIRE
FIRE comes in sizes. Lean FIRE means retiring on a tight budget, often under about $40,000 a year for a household, with little room for travel or surprises. Fat FIRE means a comfortable or even generous lifestyle, commonly $100,000 a year or more. Regular FIRE sits in between, and some people call the space between regular and fat "Chubby FIRE". There are no official cut-offs; the labels are relative to where you live and what you need.
Because the portfolio target is about 25 times spending, the gap between them is huge. Lean FIRE on $35,000 needs $875,000, while Fat FIRE on $120,000 needs $3 million. The calculator shows how many extra working years each step up costs at your current saving pace.
Picking your level
Lean FIRE gets you out sooner but leaves little margin, so a bad market or a health cost can force a return to work. Fat FIRE takes longer but builds in comfort and resilience. Many people aim for regular FIRE with a plan for flexible spending: cutting back toward lean in bad years and spending more in good ones.
The default example
With $200,000 invested, $3,000 added each month and a 5% real return, Lean FIRE at $35,000 a year needs $875,000 and arrives in about 11 years. Regular FIRE at $60,000 needs $1.5 million and takes about 18 years, and Fat FIRE at $120,000 needs $3 million and takes about 28 years.
Doubling spending from regular to fat adds about ten years, while cutting from regular to lean saves about seven. Many people find a target between lean and regular, with room to spend more once the portfolio is safely ahead, a good balance.
Common questions
What is considered Lean FIRE?
Generally retiring on a minimal budget, often below roughly $40,000 a year for a household in the US.
What is Fat FIRE?
Retiring with a generous budget, commonly $100,000 or more a year, which needs a portfolio of $2.5 million or more.
Which is best?
It depends on your costs and comfort with risk. Many aim between the two with flexible spending.
This calculator gives estimates for planning. Real returns, rates and prices change, so treat the result as a guide rather than a promise. Read how we build and check our calculators.