FIRE Calculator (Financial Independence & Retire Early)
See how long it might take to reach financial independence based on your savings, investment returns, spending, and withdrawal rate.
This is an educational tool to help you understand your path to FIRE, not a guarantee of future results.
Last updated: February 9, 2026
Finding Your Financial Independence Number
The FIRE calculator answers the question everyone pursuing financial independence asks: how much do I actually need, and when will I get there? FIRE—Financial Independence, Retire Early—isn't about extreme frugality. It's about knowing your number and building a realistic path to reach it.
The most common mistake? Using vague rules like "save 25x your expenses" without running the actual math on your situation. Your timeline depends on your starting point, savings rate, expected returns, and spending—not generic advice.
Enter your current portfolio, monthly contributions, expected investment returns, and annual spending. The calculator shows your FIRE number (the portfolio that sustains you indefinitely), when you'll hit it at your current pace, and what adjustments could accelerate the timeline.
What Drives Your FIRE Timeline
Annual spending is the most important input. Your FIRE number equals your spending divided by your safe withdrawal rate. Spending $50,000/year with a 4% rate means you need $1,250,000. Spending $80,000/year means $2,000,000. Small spending changes have massive impacts.
Safe withdrawal rate (SWR) is typically 4%, based on research showing a 4% annual withdrawal (adjusted for inflation) historically lasts 30+ years. More conservative planners use 3.5% or 3%; those with flexibility or other income sources might use 4.5%.
Current portfolio balance gives you a head start. Someone with $200,000 already invested is years ahead of someone starting from zero, even if they save the same amount monthly.
Monthly contributions determine your savings rate—the biggest lever after spending. A 50% savings rate cuts your timeline nearly in half compared to 25%.
Expected return should be realistic. Historical stock returns average ~7% after inflation, but markets vary wildly. Use 5-7% for conservative estimates. If markets beat expectations, you'll reach FI sooner.
Other income at FI (Social Security, pension, rental income) reduces how much your portfolio needs to cover. $20,000/year in Social Security at age 62 means your portfolio only needs to cover $30,000 instead of $50,000.
Two Paths to Financial Independence
Example 1: Aggressive Saver Starting Young
Inputs: Age 28, current portfolio $50,000, saves $2,500/month ($30,000/year), spending $40,000/year, expects 6% real returns, 4% withdrawal rate.
Result: FIRE number is $1,000,000. At this savings rate and return assumption, projected FI age is approximately 43 (15 years).
Interpretation: A 43% savings rate (on ~$70,000 income) creates a clear path to FI in your early 40s. The $50,000 head start accelerates the timeline by about 2 years compared to starting at zero.
Example 2: Late Starter with Higher Income
Inputs: Age 42, current portfolio $200,000, saves $4,000/month ($48,000/year), spending $70,000/year, expects 6% real returns, 4% withdrawal rate, plus $24,000/year Social Security at 67.
Result: FIRE number is $1,750,000 (only covering $70,000 - $0 = $70,000 before SS). But with SS at 67, effective FIRE number drops to $1,150,000. Projected FI age: approximately 55 (13 years).
Interpretation: Starting at 42 with $200,000 still allows for retirement 12+ years before the traditional age. The future Social Security income significantly reduces how much portfolio you need. Could work part-time from 55-67 and let portfolio grow further.
When to Use This Calculator
Use this calculator when:
- You want to know your specific FIRE number, not generic rules
- You're deciding how aggressively to save vs. enjoy life now
- You're comparing scenarios (what if I save $500 more per month?)
- You're evaluating whether Coast FIRE makes sense at your current portfolio
- You need motivation—seeing your timeline in years, not decades
This calculator won't:
- Account for market volatility (it uses constant returns)
- Model taxes on retirement withdrawals
- Calculate healthcare costs in detail
- Guarantee any outcome—these are projections, not predictions
Understanding FIRE Variations
Lean FIRE targets $25,000-$40,000/year spending, requiring $625,000-$1,000,000. Fastest path to FI but requires ongoing frugality.
Traditional FIRE targets $40,000-$80,000/year, requiring $1,000,000-$2,000,000. Balanced approach with moderate lifestyle.
Fat FIRE targets $100,000+/year, requiring $2,500,000+. Takes longer but provides more comfortable retirement.
Coast FIRE means you've saved enough that compound growth alone funds traditional retirement (age 60-65), even if you stop contributing. You can "coast" in lower-stress work.
Barista FIRE means reaching partial FI, then working part-time for health insurance and supplemental income while letting portfolio grow.
Assumptions in This Calculator
- Constant annual returns (real markets fluctuate significantly)
- Consistent monthly contributions throughout accumulation
- Spending remains stable (adjust for expected lifestyle changes)
- 4% rule applies (historically valid for 30-year retirements; longer timelines may need 3.5%)
- No taxes modeled on withdrawals
These simplifications show the math behind FIRE. Real planning should include healthcare costs, tax-efficient withdrawal strategies, and buffer for market volatility.
Sources
For Educational Purposes Only - Not Financial Advice
This calculator provides estimates for informational and educational purposes only. It does not constitute financial, tax, investment, or legal advice. Results are based on the information you provide and current tax laws, which may change. Always consult with a qualified CPA, tax professional, or financial advisor for advice specific to your personal situation. Tax rates and limits shown should be verified with official IRS.gov sources.