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Is Coast FIRE Worth It? What You Gain and What Can Go Wrong
An honest look at Coast FIRE: what you gain, how often stopping at the line works in simulated markets, and the risks most plans leave out.
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See how much you need invested today to stop saving for retirement and still retire on time.
Updated September 2026 · How we calculate
Your Coast FIRE number
$315K to go$395,332
Have this invested at 30 and it grows to $1.5M by 65 without adding anything more.
You have $80,00020% of the way
- FIRE number
- $1.5M$1,500,000
- Coast FIRE at
- age 48
- Real return
- 3.88%
Your portfolio vs. the Coast FIRE line
Your portfolioCoast FIRE lineFIRE target
| Age | Portfolio | Coast line |
|---|---|---|
| 30 | $80,000 | $395,332 |
| 35 | $228,770 | $478,294 |
| 40 | $408,760 | $578,665 |
| 45 | $626,522 | $700,100 |
| 50 | $848,750 | $847,019 |
| 55 | $1,026,863 | $1,024,768 |
| 60 | $1,242,354 | $1,239,820 |
| 65 | $1,503,066 | $1,500,000 |
How this calculator works
Coast FIRE is the point where you could stop adding to your retirement accounts and still retire on schedule. To find it, the calculator starts with your FIRE number: the portfolio that can pay for a year of retirement spending at your withdrawal rate. At $60,000 a year and 4%, that's $1.5 million.
Then it works backward. Your Coast FIRE number is the amount that, left alone, grows into that $1.5M by the age you want to retire. Everything uses a real return, meaning your expected return with inflation taken out, so every dollar figure on this page is in today's money.
Read the full methodologyFIRE number= yearly spending ÷ withdrawal rate
Real return= (1 + return) ÷ (1 + inflation) − 1
Coast FIRE number= FIRE number ÷ (1 + real return)years to retirement
Am I Coast FIRE?
You are if the money you have invested today is at least your Coast FIRE number. Some people write it as Coast FI; it's the same idea. Put your real balance into the calculator above. If the badge says you've hit Coast FIRE, you're there under those assumptions. If it shows an amount to go, the "Coast FIRE at" figure is the age you'd cross the line if you keep up your current monthly contribution.
Want a benchmark instead of your exact number? The Coast FIRE number by age table shows the target from 20 to 60, and this plan covers how to close the gap.
A worked example
Maya is 30. She figures she'll spend about $60,000 a year once she retires at 65, and she has $80,000 in her 401(k). Her FIRE number is $1.5 million, and her Coast FIRE number is $395,332.
So she's about $315K short today. If she keeps putting in $2,000 a month, she crosses the line at 48 and could stop contributing then. I'd keep going a few more years anyway. A 7% average return doesn't show up as a neat 7% every year, and the cushion is cheap when you're young.
| Item | Value |
|---|---|
| Yearly spending | $60,000 |
| FIRE number | $1,500,000 |
| Years until 65 | 35 |
| Real return | 3.88% |
| Coast FIRE number | $395,332 |
| Coast FIRE at $2,000/mo | age 48 |
Questions people ask
Short answers here. The methodology page has the long ones.
Is 7% a realistic return?
It's close to what a mostly-stock portfolio has returned before inflation over long stretches of US history, but plenty of 30-year periods did worse. If you hold a good chunk of bonds, try 5% or 6% and watch what happens. The number moves more than most people expect.
Are these numbers adjusted for inflation?
Yes. You enter spending in today's dollars, and the calculator grows your money at the real return, which is your expected return with inflation taken out. So $395,332 means $395,332 of today's buying power. Your actual account balance at 65 will show a much bigger figure, because prices will have gone up too.
What if the market drops right after I stop contributing?
Then your date slips. The calculator assumes steady average growth, and real markets don't behave that way. A 30% drop in your late 40s doesn't ruin the plan on its own, since you still have years to recover, but it can easily cost you a few of them. That's the main reason I'd keep contributing something after you cross the line, even a small amount.
Does Social Security count toward my number?
Not in this calculator. The spending figure is what your portfolio has to cover. If you expect Social Security to pay around $20,000 a year, subtract it and enter $40,000 instead of $60,000. Be realistic about when benefits start, though. If you plan to retire before they kick in, your portfolio has to cover the full amount for those years.
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