Early Retirement Calculator
Enter your current savings, income, spending, and expected investment return to find your FIRE number and how many years until you can retire early. The calculator uses inflation-adjusted returns and a custom safe withdrawal rate, then shows a year-by-year portfolio projection so you can see exactly when you cross the finish line.
Formula
Worked example
Age 30, $50,000 savings, $80,000 income, $50,000 spending, $40,000 retirement budget, 7% return, 3% inflation, 4% SWR: FIRE number = $40,000 / 0.04 = $1,000,000. Real return = (1.07/1.03) - 1 = 3.88%. Annual savings = $30,000. Starting from $50,000 and adding $30,000 per year growing at 2%, the portfolio crosses $1,000,000 in about 19 years at age 49.
What is the FIRE number and how is it calculated?
Your FIRE number is the total portfolio size you need to retire and never run out of money. It comes from flipping the 4% rule: if you can safely withdraw 4% of your portfolio each year, you need 25 times your annual retirement spending saved. So if you plan to spend $40,000 per year in retirement, your FIRE number is $40,000 / 0.04 = $1,000,000. You can adjust the withdrawal rate in this calculator. A 3.5% rate gives you 28.6x your spending and more buffer for a 40- or 50-year retirement, while 4.5% gives 22.2x for a shorter horizon.
How the calculator works
The calculator simulates your portfolio year by year. It takes your current savings, adds your annual savings (income minus spending), and applies your real (inflation-adjusted) investment return. Because all amounts are in today's dollars, you can compare your FIRE number directly to your retirement budget without worrying about future price levels. The income growth rate lets you model raises or a growing business - your savings amount compounds by that rate each year, which often cuts years off the timeline. The year-by-year table and chart show exactly when your portfolio crosses your FIRE target.
The 4% rule and safe withdrawal rates
The 4% rule comes from the Trinity Study (1998) by three Trinity University professors who analyzed 30-year retirement windows across decades of US stock and bond market data. They found that a portfolio of roughly half stocks and half bonds, with 4% annual withdrawals adjusted for inflation, had a very high historical success rate over 30 years. For early retirees who may spend 40 or 50 years in retirement, many planners suggest 3% to 3.5% for extra safety. If you expect significant other income (Social Security, rental income, pensions), a higher withdrawal rate may be appropriate since you will not need to draw as much from the portfolio.
FIRE variants: Lean, Fat, Barista, and Coast FIRE
FIRE is not one-size-fits-all. Lean FIRE means retiring on a minimal budget, often under $40,000 per year, which requires a smaller nest egg but demands disciplined frugality. Fat FIRE is retiring with a generous budget, sometimes $100,000 or more per year, requiring a much larger portfolio but allowing a comfortable lifestyle. Barista FIRE means leaving your main career but doing part-time or low-stress work to cover some expenses, so your portfolio only needs to fund the gap. Coast FIRE is the point where your existing savings, left to grow without additional contributions, will reach your FIRE number by traditional retirement age - meaning you can coast from here without saving more.
Savings rate and years to retirement
| Savings rate | Years to retirement | Retirement profile |
|---|---|---|
| 10% | ~43 years | Traditional |
| 20% | ~37 years | Standard FIRE path |
| 30% | ~28 years | Lean FIRE |
| 40% | ~22 years | FIRE-focused |
| 50% | ~17 years | Aggressive FIRE |
| 60% | ~12 years | Very aggressive |
| 70% | ~8.5 years | Extreme FIRE |
Approximate years to FIRE from a zero starting balance, assuming a 5% real return and retirement spending equal to current spending. Based on the 4% rule.
Frequently asked questions
What is a good savings rate for early retirement?
The higher, the better. A 50% savings rate puts you on track to retire in roughly 17 years from a zero starting balance. At 30% it takes closer to 28 years, and at 10% it takes about 43 years. The key insight is that your savings rate affects both sides of the equation: a higher rate means more money going in and also fewer years of spending to fund, because your lifestyle costs less.
What investment return should I use?
A 7% nominal (before inflation) or roughly 4% real (after inflation) annual return is a commonly used long-run estimate for a diversified stock portfolio based on historical US market data. More conservative investors use 5-6% nominal. Bonds and other assets lower the expected return but also reduce volatility. This calculator defaults to 7% nominal and 3% inflation, giving about a 3.9% real return.
Should I use the 4% rule or something lower?
The 4% rule was validated for 30-year retirements. If you retire at 40 and expect to live to 90, you need the portfolio to last 50 years. Most researchers and planners suggest using 3% to 3.5% for very long retirements. You can change the safe withdrawal rate in this calculator to see how it shifts your FIRE number and timeline.
Does the calculator account for inflation?
Yes. The calculator converts your nominal investment return to a real (inflation-adjusted) return and runs all projections in today's dollars. This means your FIRE number, retirement budget, and portfolio values are all comparable without needing to adjust for future price levels.
What counts as investable savings?
Count brokerage accounts, 401(k), 403(b), IRA, Roth IRA, and other investment accounts. Do not count your primary residence, cash in checking accounts beyond an emergency fund, or illiquid assets like private business equity. If you plan to use a pension, Social Security, or rental income in retirement, you can reduce your planned retirement spending by that amount before entering it in the calculator.
Why does my FIRE number seem too high?
The FIRE number is meant to sustain withdrawals indefinitely. It looks large because it is - a $1 million portfolio generating 4% a year is $40,000, every year, without depleting the principal (under historical return assumptions). If the number feels unreachable, try reducing your planned retirement spending first. Cutting $5,000 per year from your retirement budget cuts your required portfolio by $125,000 at the 4% rate.