Why This Calculator Changes Everything
Coast FIRE is the sweet spot where your existing investments will grow to fully fund your retirement—without you adding another dollar. Our Coast FIRE Calculator helps you:
- 💰 Find Your Coast FIRE Number — know exactly how much you need today to coast to retirement
- 📈 Track Your Progress — see how close you are to financial independence
- 🏖️ Plan Your Freedom — discover when you can stop aggressive saving and start living more freely
- 📊 Visualize Your Growth — watch your portfolio grow to your retirement target over time
- 🔒 100% Private — all calculations run locally in your browser
What Is Coast FIRE? (The Short Version)
Coast FIRE means you’ve saved and invested enough that your existing portfolio—left alone to grow at a normal market rate—will reach your retirement number on its own, without any additional contributions.
Think of it as hitting the savings finish line early. Your money does the rest of the work through the magic of compound interest.
Once you hit your Coast FIRE number:
- You can stop saving for retirement entirely
- You can take lower-paying but more fulfilling jobs
- You can work fewer hours or pursue passion projects
- You’re no longer stressed about hitting a specific savings target each month
You’re not necessarily retired—you’re just coasting.
The Simple Math Behind Coast FIRE
Step 1: Your Full FIRE Number
FIRE Number = Annual Retirement Spending ÷ Safe Withdrawal Rate
If you need $50,000 per year and use the 4% rule, your full FIRE number is $1,250,000.
Step 2: Your Coast FIRE Number
Coast FIRE Number = FIRE Number ÷ (1 + Expected Return)^Years to Retirement
Here’s a real example:
| Variable | Value |
|---|---|
| Annual Retirement Spending | $50,000 |
| Safe Withdrawal Rate | 4% |
| FIRE Number | $1,250,000 |
| Current Age | 30 |
| Retirement Age | 65 |
| Years to Retirement | 35 |
| Expected Return | 7% |
| Coast FIRE Number | $1,250,000 ÷ (1.07)^35 = $117,000 |
If you have $117,000 invested at age 30, you can stop saving and still have $1.25 million by age 65. That’s the power of compound interest.
Coast FIRE in Real Life: See the Scenarios
| Scenario | Age | Current Savings | Return | Retirement Spending | Coast FIRE Number | Status |
|---|---|---|---|---|---|---|
| Early Starter | 25 | $50,000 | 7% | $40,000 | $82,000 | Not yet |
| On Track | 35 | $200,000 | 7% | $60,000 | $221,000 | Approaching |
| Coast Achieved | 40 | $300,000 | 7% | $50,000 | $310,000 | ✅ You’re there! |
| Coast Exceeded | 45 | $500,000 | 7% | $50,000 | $221,000 | ✅ Well ahead |
How to Use This Calculator
Getting your Coast FIRE number is quick and straightforward:
- Enter your current age — how old you are right now.
- Set your target retirement age — when you want to stop working entirely.
- Enter your current retirement savings — what you’ve saved so far.
- Enter your expected annual retirement spending — how much you’ll need each year in retirement.
- Set your safe withdrawal rate — 4% is the standard, but you can adjust it.
- Enter your expected annual return — a realistic long-term rate (7% is common for stock-heavy portfolios).
- View your results instantly — see your Coast FIRE number, your progress, and your timeline.
The tool updates in real time—no “Calculate” button required.
Who Benefits From This Calculator?
- Young professionals — who want to know if they’re on track to coast
- Mid-career savers — looking to reduce stress and enjoy life more
- Anyone — dreaming of financial independence
- Career-changers — wanting to take a lower-paying, more fulfilling job
- Curious savers — wondering “how much is enough to just let it grow?”
Common Questions About Coast FIRE
What is Coast FIRE in plain English?
It’s the point where your existing investments will grow to fully fund your retirement—without you adding another dollar. You can stop saving and let compound interest do the rest. You’re not retired yet, but you’re no longer stressed about saving.
How is Coast FIRE calculated?
Coast FIRE Number = FIRE Target ÷ (1 + Return Rate)^Years to Retirement
This tells you how much you need invested today to reach your retirement goal through compound growth alone.
What’s the FIRE number?
It’s the total amount you need to retire. You calculate it as: Annual Retirement Spending ÷ Safe Withdrawal Rate. Using the 4% rule, if you need $50,000 per year, your FIRE number is $1,250,000.
What’s a good Coast FIRE progress percentage?
- 100% — you’ve reached Coast FIRE
- Below 100% — you still need to save more
- Above 100% — your portfolio is already on track to exceed your retirement goal
Is the 4% safe withdrawal rate still valid?
The 4% rule is a widely used guideline based on historical market data. Many experts suggest 3.5% to 4% for longer retirements. You can adjust this rate in the calculator to match your risk tolerance.
What if the market doesn’t perform as expected?
That’s a valid concern. The calculator uses a fixed return assumption, but real markets fluctuate. Most Coast FIRE planners use a conservative return estimate (like 6-7%) and monitor their progress over time. If markets underperform, you can always choose to save a little more.
🏖️ Quick Tip: Coast FIRE isn’t about quitting work entirely—it’s about having the freedom to choose work you love without worrying about saving for retirement. Once you hit your Coast FIRE number, you can relax, work less, or pursue passion projects. Your future is already taken care of.