FIRE Calculator: Find Your Financial Independence Number
Calculate exactly how much you need to retire early. Enter your expenses, savings rate, and investment returns to see your FIRE number and timeline for Lean FIRE, Regular FIRE, Fat FIRE, and Coast FIRE.
Your FIRE Numbers
How This Calculator Works
The FIRE (Financial Independence, Retire Early) number is the amount you need invested to live off your portfolio indefinitely. It's calculated using the 4% rule (or your chosen withdrawal rate).
FIRE Variants Explained
- Lean FIRE: Minimal expenses lifestyle (60% of regular expenses)
- Regular FIRE: Current lifestyle maintained
- Fat FIRE: Comfortable lifestyle with extras (150% of regular expenses)
- Coast FIRE: Amount needed now that will grow to your FIRE number by traditional retirement age
Assumptions
- Returns are inflation-adjusted (real returns)
- Traditional retirement age is 65 for Coast FIRE
- Expenses remain constant (inflation-adjusted)
How to Use This FIRE Calculator
This FIRE calculator helps you determine your Financial Independence, Retire Early (FIRE) number—the amount you need invested to cover your living expenses indefinitely without working. Enter your current age, target retirement age, annual expenses, current savings, annual savings rate, and expected investment returns. The calculator shows your FIRE number, years to reach it, and the monthly savings needed to hit your goal.
Understanding the FIRE Formula
Your FIRE number is calculated using the safe withdrawal rate (typically 4%, based on the Trinity Study). The formula is:
Example: $40,000 ÷ 0.04 = $1,000,000
This means if you spend $40,000 per year, you need $1 million invested to withdraw 4% annually without depleting your portfolio over a 30+ year retirement.
FIRE Variants Explained
Not everyone pursues the same version of financial independence. Here's what each variant means:
Lean FIRE
Achieving financial independence on a minimalist budget (typically 60% of average expenses). Best for those comfortable with frugal living and lower spending. Learn more about Lean FIRE →
Regular FIRE
The standard approach—saving 25x your current annual expenses to maintain your existing lifestyle without working. This is what most people mean when they say "FIRE."
Fat FIRE
Financial independence with a comfortable or luxury lifestyle (150%+ of average expenses). Requires more savings but provides more cushion and flexibility. Compare Lean vs Fat FIRE →
Coast FIRE
Having enough invested today that, with no additional contributions, compound growth will reach your FIRE number by traditional retirement age (65). You still work, but only to cover current expenses. Read our Coast FIRE guide →
Frequently Asked Questions
What is a good FIRE number?
Your FIRE number depends entirely on your annual expenses. A "good" FIRE number is one that covers your actual spending. For someone spending $30,000/year, a FIRE number of $750,000 works. For someone spending $80,000/year, they need $2 million. Focus on your real expenses, not arbitrary targets.
Is the 4% rule still valid?
The 4% rule comes from the 1998 Trinity Study, which found that a 4% withdrawal rate had a high probability of lasting 30 years across historical market conditions. For early retirees planning 40-50 year retirements, some financial planners suggest using 3.5% or 3.25% for extra safety. This calculator lets you adjust the withdrawal rate to see how it affects your FIRE number.
What return should I assume for FIRE calculations?
The default 7% represents the historical inflation-adjusted return of a diversified stock portfolio. Conservative planners use 5-6%; optimistic planners might use 8%. Since FIRE timelines span decades, even small differences in assumed returns significantly impact your projected timeline. Learn about index fund investing →
How do I speed up my path to FIRE?
There are two levers: increase savings and decrease expenses. Reducing expenses works double—you save more now AND need less in retirement. A $500/month expense reduction means $6,000 more saved annually AND $150,000 less needed for your FIRE number. Read our complete FIRE guide →
Should I include Social Security in my FIRE calculations?
Most FIRE planners treat Social Security as a bonus rather than counting on it. If you retire at 40, you won't receive Social Security for 22+ years. However, once you do receive it, your required portfolio withdrawals decrease significantly. This calculator doesn't include Social Security to provide a conservative baseline.
What about healthcare costs before Medicare?
Healthcare is the biggest expense for early retirees. Make sure your annual expenses include realistic healthcare costs—often $500-1,500/month for a family before age 65. Some pursue Barista FIRE specifically to access employer health insurance through part-time work.