FIRE Calculator & Coast FIRE Calculator

About This FIRE Calculator & Coast FIRE Calculator

This free FIRE calculator helps you figure out your Financial Independence, Retire Early (FIRE) number — exactly how much money you need to save to quit your job and live off your investments. Whether you're aiming for Coast FIRE, Barista FIRE, Fat FIRE, or just traditional early retirement, this calculator gives you a clear timeline and actionable numbers.

Based on the famous 4% rule from the Trinity Study, this calculator uses the standard FIRE formula: your FIRE number equals your annual expenses multiplied by 25. Enter your current age, annual spending, current savings, and how much you save each year, and we'll show you exactly when you can pull the plug on your 9-to-5.

What Is FIRE?

FIRE stands for Financial Independence, Retire Early — a movement that started gaining popularity in the 2010s, fueled by books like "Your Money or Your Life" and the Mr. Money Mustache blog. The core idea is simple: save and invest aggressively (often 50-70% of your income), reach a "FIRE number" of 25x your annual expenses, then retire in your 30s, 40s, or 50s — decades before the traditional retirement age of 65.

The FIRE movement isn't just about quitting work forever. For many people, it's about gaining freedom — the freedom to take a lower-paying job you love, start a business, volunteer, or spend more time with family. You don't have to stop working entirely; you just stop having to work.

The 4% Rule: How It Works

The 4% rule comes from the famous 1998 Trinity Study, which analyzed 30-year periods of stock and bond returns dating back to 1926. The study found that if you withdraw 4% of your portfolio in the first year of retirement, then adjust that withdrawal for inflation each subsequent year, your money would likely last at least 30 years without running out.

This is why the FIRE number is calculated as annual expenses × 25 — because 4% of 25x your expenses equals exactly your annual spending. For example, if you spend $50,000 per year, your FIRE number is $1,250,000. Withdrawing 4% of $1.25M = $50,000 per year, which covers your expenses.

Keep in mind: the 4% rule is a guideline, not a guarantee. It worked well over 30-year periods in the U.S. historical data, but some experts argue that today's high valuations and low bond returns might warrant a more conservative 3-3.5% withdrawal rate. This calculator uses 4% as the default, but you can adjust it.

Types of FIRE: Coast, Barista, Fat, Lean, Chubby

The FIRE movement has evolved into several different flavors, depending on how much you want to save and what kind of retirement lifestyle you're aiming for:

• Coast FIRE: You've saved enough in your retirement accounts that, even if you stop contributing now, the money will grow enough (at historical average returns) to cover your expenses when you reach traditional retirement age. You can "coast" — work a low-stress job just to cover living expenses, without worrying about saving for retirement. This is the most achievable FIRE milestone for most people in their 30s and 40s.
• Barista FIRE: You have enough saved to cover part of your living expenses, but not all of it. You keep working a part-time or low-stress job (like a barista, hence the name) to cover the rest. This lets you quit your high-pressure 9-to-5 without fully retiring.
• Lean FIRE: You've reached full FIRE, but with a very frugal lifestyle. Your annual expenses are low (maybe $25,000-$35,000/year), so your FIRE number is smaller and easier to hit. Lean FIRE requires strict budgeting and minimalism.
• Fat FIRE: You've reached FIRE with a high lifestyle — your annual expenses are $100,000+ per year, so your FIRE number is $2.5M+. Fat FIRE takes longer to achieve but lets you live a comfortable, luxurious retirement.
• Chubby FIRE: A middle ground between Lean and Fat FIRE — your spending is moderate (maybe $60,000-$80,000/year), not super frugal but not extravagant either.

How to Calculate Your Coast FIRE Number

Coast FIRE is often the first big milestone people hit. The idea: you've saved enough that you don't need to save any more for retirement — your existing savings will compound enough over the next decades to grow into your full FIRE number by age 65.

To calculate your Coast FIRE number: take your full FIRE number, then figure out how much you'd need to invest today so it grows to your FIRE number by age 65 at an assumed 7% annual return. For example, if you're 35 and your FIRE number is $1.25M, you'd need about $320k today to grow to $1.25M in 30 years at 7% annual returns. That's your Coast FIRE number.

Once you hit Coast FIRE, you can stop saving for retirement entirely! You can work a job you enjoy (even if it pays less), just to cover your day-to-day expenses. Your retirement nest egg is already set — it just needs time to grow.

How Long Does It Take to Reach FIRE?

How fast you reach FIRE depends almost entirely on your savings rate — the percentage of your income you save. Here's a rough guide (assuming 7% annual returns):

• 10% savings rate: ~51 years to FIRE (basically traditional retirement)
• 20% savings rate: ~37 years
• 30% savings rate: ~28 years
• 40% savings rate: ~22 years
• 50% savings rate: ~17 years
• 60% savings rate: ~12 years
• 70% savings rate: ~9 years
• 80% savings rate: ~7 years

The higher your savings rate, the faster you reach FIRE — and the relationship is exponential. Doubling your savings rate from 20% to 40% doesn't cut your time in half; it cuts it by 15 years! This is why the FIRE movement emphasizes aggressive saving — it's the fastest lever you have.

Common FIRE Mistakes to Avoid

• Underestimating healthcare costs: This is the biggest risk for early retirees! Health insurance in the U.S. is expensive if you're not covered by an employer. Make sure you factor in ACA marketplace premiums, or plan to work a part-time job that offers benefits (Barista FIRE style).
• Ignoring taxes: Withdrawals from traditional 401(k)s and pre-tax IRA accounts are taxed as ordinary income. Don't forget to factor in taxes when calculating your withdrawal rate — your $50,000 withdrawal might only be $38,000 after taxes.
• Sequence of returns risk: If the stock market crashes early in your retirement, your portfolio might not recover. This is why many FIRE followers keep 1-2 years of expenses in cash/bonds, so they don't have to sell stocks at a loss.
• Lifestyle inflation: As your income goes up, don't let your spending go up with it. The key to FIRE is keeping your expenses low while your income grows. If you get a raise, put the extra money into savings, not into a bigger house or nicer car.
• Not having fun along the way: FIRE is a marathon, not a sprint. If you're so frugal that you're miserable, you won't stick with it. Budget for fun — hobbies, travel, eating out — so you actually enjoy the journey, not just the destination.

Frequently Asked Questions

What is a good FIRE number?

Your FIRE number is simply your annual expenses multiplied by 25 (based on the 4% rule). If you spend $40,000 per year, your FIRE number is $1,000,000. If you spend $100,000 per year, it's $2,500,000. There's no one "right" number — it depends entirely on your lifestyle. Lean FIRE might be $750k-$1M, Fat FIRE might be $3M+.

How much do I need to retire at 40?

To retire at 40 with a $50,000/year lifestyle, you'd need about $1.25M invested. But remember: if you retire at 40, your money needs to last 50+ years, not 30. The 4% rule was tested over 30-year periods. For a 50+ year retirement, many experts recommend a more conservative 3-3.5% withdrawal rate — which means you'd need $1.43M-$1.67M instead of $1.25M.

What is Coast FIRE, exactly?

Coast FIRE means you've saved enough in your retirement accounts that, even if you stop contributing right now, your money will grow (at historical average returns) to your full FIRE number by age 65. Once you hit Coast FIRE, you can "coast" — work any job you want just to cover your living expenses, without worrying about saving for retirement. Your nest egg is already set; it just needs time to grow.

Is the 4% rule still safe in 2024?

That's debated. Some experts argue that today's high stock market valuations and low bond yields mean the 4% rule might not last 30 years going forward. They recommend a more conservative 3-3.5% withdrawal rate. On the other hand, other analysts point out that the Trinity Study already included worst-case scenarios like the Great Depression and the 1970s stagflation, and 4% still held up. A common middle ground: use 4% as a planning number, but be flexible — if the market drops, cut back on spending temporarily.

Can I retire early with $1 million?

Yes — if your annual expenses are $40,000 or less. $1M × 4% = $40,000 per year. If you live in a low-cost area, have paid off your mortgage, and don't have kids in expensive daycare, $1M is enough to retire on. If you're spending $80,000+ per year, you'd need $2M+. It all comes down to your expenses, not your income.

Frequently Asked Questions (More Answers)

What's the difference between FIRE and regular retirement?

The biggest difference is age. Regular retirement happens at 65-67, when you can collect Social Security and Medicare. FIRE happens in your 30s, 40s, or 50s — decades earlier. That means you have more years of retirement to fund, and you'll have to cover your own health insurance until Medicare kicks in at 65. FIRE isn't just "retirement early" — it's a whole different financial strategy.

Do I need to pay off my mortgage before FIRE?

Not necessarily, but it helps. A paid-off mortgage drastically reduces your monthly expenses, which lowers your FIRE number. Many FIRE followers choose to pay off their mortgage before retiring, because it eliminates their biggest monthly expense and gives them peace of mind. But it's not required — if your investments are earning more than your mortgage interest rate (after tax deduction), it might make sense to keep the mortgage and invest the extra cash.

How does Social Security fit into FIRE?

Social Security is a wild card for early retirees. You can't collect it until age 62 (early) or 67 (full retirement age). That means if you retire at 45, you'll need to cover 17-22 years of expenses entirely from your investments before Social Security kicks in. Many FIRE plans count Social Security as a "bonus" later in life — they plan their withdrawal rate to cover expenses without Social Security, then use the Social Security checks to extend their portfolio or fund fun stuff.

What is the FIRE movement's average net worth?

It varies a lot by age and location. People in the FIRE community on Reddit (r/financialindependence) range from people just starting out (saving their first $10k) to multi-millionaires. The median FIRE number for someone in their mid-30s is probably around $500k-$1M, depending on their expenses. The key is that everyone's path is different — don't compare your journey to someone else's.

Is FIRE only for high earners?

No! While high income makes it faster, FIRE is really about savings rate, not income. Someone making $60,000/year who saves 50% ($30,000/year) can reach FIRE just as fast as someone making $200,000/year who saves the same $30,000. In fact, many high earners struggle with FIRE because lifestyle inflation eats up their raises. The FIRE movement is for anyone who wants to take control of their time and money — regardless of income level.