FIRE Calculator 2026 – Plan Your Early Retirement With Confidence

The FIRE Formula Explained (25× Rule + 4% Rule)

At the core of FIRE planning are two simple principles.

FIRE Number Formula

FIRE Number = Annual Expenses × 25

This assumes a long-term withdrawal rate of about 4 percent.

The 4% Rule

The 4% rule suggests that you can withdraw 4 percent of your portfolio each year, adjusted for inflation, with a high probability of your money lasting 30 years or more.

Examples

Annual Expenses	FIRE Number
$40,000	$1,000,000
$60,000	$1,500,000
$80,000	$2,000,000

These numbers provide a starting point, not a guarantee. Real FIRE planning also considers flexibility, market volatility, and lifestyle choices.

What Is Your FIRE Number?

Your FIRE number is the total amount of invested assets required to fund your lifestyle indefinitely.

It depends almost entirely on expenses, not income.

If you spend:

• $50,000 per year → FIRE number ≈ $1.25 million
• $75,000 per year → FIRE number ≈ $1.875 million

Lower expenses reduce the required portfolio. Higher expenses increase it.

This is why FIRE planning focuses first on controlling spending, not chasing income alone.

Why Your Savings Rate Matters More Than Income

Your savings rate is the most powerful variable in FIRE planning.

A higher savings rate:

• Reduces current expenses
• Lowers your FIRE number
• Accelerates compounding

Approximate Impact of Savings Rate

Savings Rate	Typical Time to FIRE
10%	40–50 years
25%	30–35 years
50%	15–20 years
70%	8–10 years

This is why many people reach FIRE on moderate incomes by keeping expenses low and investing consistently.

Investment Growth Assumptions Used

The calculator uses long-term average growth assumptions, not best-case scenarios.

Historically:

• Broad stock markets have returned about 7 percent after inflation
• Diversification reduces volatility but not short-term risk

These assumptions are meant to be conservative enough to plan responsibly, while still reflecting long-term market behavior.

Inflation and FIRE Planning (2026 Update)

Check official inflation data (BLS)

The Biggest Risk Most FIRE Plans Ignore: Sequence of Returns

Sequence of returns risk refers to poor market performance early in retirement.

Early losses matter more because withdrawals lock them in.

To manage this risk:

• Maintain flexibility in spending
• Avoid rigid withdrawal rules
• Keep a buffer or cash reserve

The FIRE Calculator uses baseline assumptions, but successful early retirement also depends on adaptability.

Is the 4% Rule Always Safe for FIRE?

The 4% rule was designed for 30-year retirements, not necessarily 50-year early retirements.

Some FIRE planners choose:

• 3.5 percent withdrawals for extra safety
• Dynamic withdrawals based on market conditions
• Part-time income to reduce drawdowns

The calculator uses 4 percent as a planning benchmark, not a promise.

Which FIRE Calculator Should You Use?

Use the main calculator to understand the math, then refine your plan with the calculator that matches your goals.

Passive Income and Early Retirement

Passive income can reduce pressure on your investment portfolio.

Common sources include:

• Dividends
• Rental income
• Royalties or business income

Example:
If your annual expenses are $40,000 and passive income covers $15,000, your portfolio only needs to fund the remaining $25,000.

This flexibility improves FIRE sustainability.

Common FIRE Planning Mistakes