FIRE Number

What Is Your Number?

Every financially independent person has a number — the size of the investment portfolio at which they no longer need to work to sustain their lifestyle. For most people it is somewhere between 25 and 33 times their annual expenses. The math behind it is surprisingly robust: a portfolio of that size, invested in a diversified mix of stocks and bonds, has historically generated enough return to fund withdrawals indefinitely without depleting the principal.

The harder question is how long it takes to get there — and that answer depends almost entirely on one variable: your savings rate. Not your income. Not your investment returns. The percentage of your income you save and invest each year is the single biggest determinant of when you reach financial independence, and the relationship is non-linear. Going from a 10% savings rate to a 30% savings rate does not take three times as long — it cuts your timeline by more than half. This calculator shows you exactly where you stand, how far away your number is, and what the leverage points are.

FIRE Number Calculator

Find your Financial Independence number, how long until you reach it, and whether you have already hit Coast FIRE

FIRE variant
Regular FIREFull financial independence at your current lifestyle. The 4% rule means you need 25x your annual expenses invested.
Lean / Fat / Barista FIRELean uses lower expenses and a smaller target. Fat maintains a high-income lifestyle. Barista means semi-retiring with part-time income covering basic expenses.
Coast FIREYou have enough invested that compound growth alone will reach your FIRE number by retirement age - even if you stop contributing now.
Which type of FIRE are you targeting?
Regular FIRE: full financial independence at your current lifestyle. The 4% rule means you need 25x your annual expenses invested.
Your situation
Annual expensesYour most important input. Your FIRE number is a direct multiple of your expenses - reducing spending has a double effect, lowering the target and increasing savings.
Current portfolioThe value of all invested assets today - brokerage accounts, 401k, IRA, etc. This is your starting point toward your FIRE number.
Annual savingsHow much you contribute to investments each year. Combined with returns, this drives how fast you reach your number.
Current age 35
Annual expenses (current) $60,000
Current portfolio value $150,000
Annual savings (contributions) $24,000
Annual income (for savings rate) $100,000
Assumptions
Expected annual return7% is the commonly used long-term real return for a diversified stock portfolio (S&P 500 historical average). Adjust down for more conservative allocations.
Safe withdrawal rate (SWR)The percentage of your portfolio you can withdraw annually without running out of money. 4% is the Trinity Study standard for 30-year retirements. The calculator auto-adjusts this based on your retirement length.
Life expectancy & retirement ageTogether these determine your retirement length, which drives the recommended SWR. A 45-year retirement needs a lower SWR than a 20-year one.
Expected annual return 7.0%
Inflation rate 3.0%
Safe withdrawal rate 4.0%
Target retirement age 55
Life expectancy 90 yrs
Social Security
Monthly SS benefitYour estimated benefit at your planned claiming age. Look this up at ssa.gov. This reduces your FIRE number because your portfolio only needs to cover the gap between expenses and SS income.
SS claiming ageClaiming at 62 reduces your benefit by 30%. Waiting to 70 increases it by 24% above the Full Retirement Age amount. Every year of delay adds roughly 8%.
Include Social Security income?

FIRE Number Calculator - Results Summary

Your FIRE number
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25x annual expenses at 4% SWR
0% there-
Calculating...
Years to FIRE
at current savings rate
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FIRE age
projected retirement age
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Savings rate
% of income saved
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Monthly savings needed
to hit target retirement age
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Coast FIRE number
needed now to coast to 65
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Annual spend in retirement
inflation-adjusted at FIRE age
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Retirement length
years your portfolio must last
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Chart view
Portfolio value
FIRE number (inflation-adj.)
Coast FIRE threshold
Disclaimer: Results are estimates based on the inputs provided and the Trinity Study / Bengen 4% rule research. The 4% safe withdrawal rate is based on historical US market data and is not guaranteed for future periods, especially for retirements longer than 30 years. Sequence-of-returns risk, healthcare costs, and tax treatment are not fully modeled. This calculator is for educational purposes only and does not constitute financial advice. Consult a qualified financial planner before making retirement decisions.

Sources: Bengen (1994) - original safe withdrawal rate research. Cooley, Hubbard, Walz (1998, updated 2009) - Trinity Study portfolio survival rates. Mr. Money Mustache - savings rate to retirement years relationship. ERN (Early Retirement Now) - sequence of returns analysis.