The FIRE Movement: How to Calculate Your Number
Published Apr 13, 2026 · 6 min read
FIRE (Financial Independence, Retire Early) means having enough invested that your portfolio can cover your living expenses indefinitely. Here's how to calculate your number.
The Basic Formula
FIRE Number = Annual Expenses Γ 25
This is based on the 4% safe withdrawal rate from the Trinity Study.
This is based on the 4% safe withdrawal rate from the Trinity Study.
If you spend $50,000/year, your FIRE number is $1,250,000. At 4% withdrawal, that generates $50,000/year.
FIRE Variants
| Type | Annual Spending | FIRE Number |
|---|---|---|
| Lean FIRE | $30,000-$40,000 | $750K-$1M |
| Regular FIRE | $50,000-$70,000 | $1.25M-$1.75M |
| Fat FIRE | $100,000+ | $2.5M+ |
| Coast FIRE | Varies | Invest enough early, then coast |
The Savings Rate Is Everything
At a 50% savings rate, you can reach FIRE in ~17 years. At 70%, it takes ~8.5 years. The savings rate matters far more than investment returns.
Try it: Use our FIRE Calculator to find your number and see how many years until you reach financial independence.