Lean FIRE Calculator

Retire early on less. Calculate your frugal financial independence number.

$ /month
% (25x)

To cover $2,500/month in retirement:

$750,000 Lean FIRE number
$30,000/year annual spending
$2,500/mo safe withdrawal $82/day budget
You saved more of your income?
Retire 4 years earlier

Lean FIRE by Expense Level

Monthly Annual Lean FIRE Number Level
$1,500 $18,000 $450,000 Ultra-Lean
$2,000 $24,000 $600,000 Very Lean
$2,500 $30,000 $750,000 Lean
$3,000 $36,000 $900,000 Lean
$3,333 $40,000 $1,000,000 Lean Threshold

What is Lean FIRE?

Lean FIRE is financial independence on a budget. It means having enough invested to retire early while living on $40,000/year or less (some definitions use $50,000). At the 4% withdrawal rate, that's a portfolio of $1,000,000 or under.

The appeal is straightforward: smaller target, faster arrival. Someone pursuing Lean FIRE might hit their number in 10-15 years while their Fat FIRE counterpart is still grinding away. You trade lifestyle for time—accepting fewer luxuries in exchange for more years of freedom.

But Lean FIRE isn't about deprivation. It's about intentionality. Lean FIRE practitioners often report higher life satisfaction than they had while earning more and spending more. When you strip away the stuff that doesn't matter, what's left is often what does.

The philosophy of Lean FIRE borrows from minimalism, voluntary simplicity, and the recognition that hedonic adaptation makes expensive lifestyles unsatisfying anyway. You get used to the fancy car within months; then it's just a car. Lean FIRE sidesteps this treadmill entirely.

Lean FIRE Numbers by Expense Level

The math is simple: annual expenses × 25 (or divided by your withdrawal rate). Here's what it looks like at typical Lean FIRE spending levels:

Monthly Spending Annual Spending Lean FIRE Number (4%) Lean FIRE Number (3.5%)
$1,500 $18,000 $450,000 $514,000
$2,000 $24,000 $600,000 $686,000
$2,500 $30,000 $750,000 $857,000
$3,000 $36,000 $900,000 $1,029,000
$3,333 $40,000 $1,000,000 $1,143,000

Notice the power of each $500/month reduction: it's $150,000 less you need to save. That could be 2-3 years off your timeline.

Is Lean FIRE Right for You?

Lean FIRE isn't for everyone. It works best if you:

  • Actually enjoy simple living: Not as a temporary sacrifice, but as your genuine preference. If you're miserable without restaurants and travel, Lean FIRE will make you miserable in retirement.
  • Live in a low cost-of-living area: $30,000/year goes much further in rural Tennessee than San Francisco. Geographic arbitrage is your friend.
  • Have paid-off housing (or very cheap rent): Housing is typically the biggest expense. Own your home outright, live with family, or find unusually cheap rent.
  • Are healthy and can stay that way: Healthcare is the wildcard. Lean budgets leave less room for expensive medical needs.
  • Don't have dependents (or have very low-cost dependents): Kids are expensive. Not impossible with Lean FIRE, but much harder.
  • Have skills to earn if needed: Lean budgets have less buffer. If something goes wrong, you may need to earn some money temporarily.

Lean FIRE Strategies

Housing: The Make-or-Break Expense

Most Lean FIRE budgets allocate $500-$1,000/month to housing. Options include:

  • Owning a paid-off home in a low-cost area
  • House hacking (renting rooms, duplex living)
  • Living abroad in LCOL countries
  • Van/RV life (increasingly popular in the FIRE community)
  • Moving to rural areas or small towns

Healthcare: The American Challenge

In the U.S., healthcare is often Lean FIRE's biggest obstacle. Strategies include:

  • ACA subsidies (significant at Lean FIRE income levels)
  • Healthcare sharing ministries (controversial but cheaper)
  • Part-time work with benefits (Barista FIRE hybrid)
  • Retiring abroad to countries with cheaper healthcare
  • Waiting until Medicare eligibility at 65

Transportation: Keep It Cheap

Lean FIRE typically means one cheap car (or no car), biking, walking, and occasional ride-sharing. Budget $100-$300/month including insurance, maintenance, and fuel.

Food: The Easy Win

Cooking at home is cheaper and often healthier. Lean FIRE food budgets typically run $200-$400/month per person. Learn to cook well and you won't feel deprived.

Risks of Lean FIRE

Less Margin for Error

A $1,000,000 portfolio can absorb a $20,000 surprise. A $500,000 portfolio feels that hit much harder. Lean FIRE leaves less buffer for:

  • Medical emergencies
  • Major home or car repairs
  • Family financial needs
  • Unexpected inflation
  • Market downturns (sequence of returns risk)

Lifestyle Inflation Risk

What if your expenses naturally creep up over time? What if you want to travel more at 50 than 40? Lean FIRE assumes your preferences stay stable, which isn't guaranteed.

Mitigation Strategies

  • Keep marketable skills current (you can always earn if needed)
  • Build a separate emergency fund (3-6 months expenses)
  • Target 10-20% above your Lean FIRE number
  • Maintain flexibility to reduce spending further if needed
  • Consider part-time work as a backup option

Frequently Asked Questions