Have you ever wondered if you really need to keep saving for retirement?
Believe it or not, you may be closer than you think to achieving your retirement goals.
That’s a very powerful realization.
Think about the options you can create for yourself if you no longer need to save a hefty chunk of your paycheck for retirement.
We recently explored some of these options while talking about the money mindset hack known as Coast FIRE.
Today, we’ll look at some specific examples of how to calculate your Coast FIRE number so you can see how you stack up.
By calculating your Coast FIRE number, you may just find that you have more options than you ever thought possible.
Let’s explore.
What is Coast FIRE?
Coast FIRE is a subset of FIRE for people who are not necessarily trying to retire early.
Instead, the idea is to aggressively fund your retirement accounts early on so you have more options as your career progresses.
The reason you’ll have options is because once you hit your projected magic retirement number, you no longer need to fund your retirement accounts.
You can sit back and let compound interest do its thing. Your retirement years are covered.
With retirement covered, you don’t need to earn as much money. You can focus more attention on your present-day self. That might mean working less hours or working the same amount but in a different job.
This is the essence of Coast FIRE: knock out retirement planning early on to create more career flexibility later.
Coast FIRE does not mean complete financial independence.
When you reach Coast FIRE, you are not financially independent because you still need money coming in to fund your current lifestyle.
But, you need less money because you no longer need to save for the important goal of retirement. That means you have earned some financial freedom, but not complete freedom.
That’s OK.
Remember, the part that separates Coast FIRE from traditional FIRE is that early retirement is not the goal.
Instead, Coast FIRE means continuing to work until normal retirement age (like age 65) but having more freedom in what you do for work.
To put a bow on it: the main money mindset benefit of Coast FIRE is that you have options once you’ve already put away enough money for retirement.
With retirement taken care of, you can:
- Switch to a lower paying job or lower stress job.
- Become a stay-at-home parent and live off of one spouse’s income.
- Start a business.
- Grow your side hustle.
- Take some time off to think about what you want to do next.
With Coast FIRE, each of these options feels safer because you’ve already fully funded your retirement.
Your Coast FIRE number is not the same as your FI number.
As we’ll explore below, your Coast FIRE number is different from your FI number (what I sometimes refer to as your magic retirement number).
Your Coast FIRE number is the amount you need saved up today to stop saving anymore for a traditional retirement. You still need to earn money to fund your current lifestyle.
Your FI number is the amount you need saved up today to retire and live completely off your investments for the rest of your life.
You’ll see below that your Coast FIRE number is usually significantly lower than your FI number.
This is especially true the further away you are from traditional retirement age. That’s because you have a longer time horizon for compound interest to do its thing.
In fact, the reason Coast FIRE is such a powerful money mindset hack is because the Coast FIRE number seems much more attainable.
This of it like this: have you ever felt that it seems impossible to save millions of dollars for retirement?
The truth is you don’t have to come up with all that money on your own. Your job is to aggressively seed your retirement accounts early on so compound interest can do the heavy lifting.
By funding your retirement accounts early in your career, you don’t need millions of dollars. You actually need way less.
Calculating your Coast FIRE number will drive this point home.

How do I calculate my Coast FIRE number?
There are some great online calculators available to figure out your Coast FIRE number.
You simply plug in a few variables, like your current age, desired retirement age, and anticipated spending in retirement. It couldn’t be easier.
The Fioneers and WalletBurst each have easy-to-use calculators that I recommend. There are plenty of others, but these two are simple to use.
What’s nice about each calculator is that you can play around with the inputs to explore various scenarios. You can also see how your Coast FIRE number is significantly lower than your FI number.
The WalletBurst calculator has a helpful graph for visualizing your progress towards Coast FIRE.
The Fioneers calculator has a nice feature where you can input other sources of passive income, like income from a rental property.
As we know, adding just one rental property to your investment portfolio can massively shrink your magic retirement number and accelerate your journey to financial freedom.
If you’re thinking about rental property investing to supplement your retirement income, check out my recent post:
Note: The Fioneers’ calculator is a Google Sheet you can download, but you need to enter your email address first. You do not need to enter an email address to use the WalletBurst calculator.
Using these calculators, let’s take a look at a few examples.
Let’s explore three different scenarios where knowing your Coast FIRE number can be very useful:
- Clarke is 35-years-old and ready for a new job.
- David is 40-years-old and worried about paying for college.
- Dorothy is 28-years-old and just paid off her student loans.
In each of these examples, we’ll assume a standard retirement age of 65 and an annual rate of return of 10% (on par with the historical results of the S&P 500).
We’ll also factor in a 3% inflation rate (the historical average in the United States).
Finally, we’ll assume a safe withdrawal rate of 4.7% in light of the updated “4% Rule.”
In case you missed it, Bill Bengen, creator of the 4% Rule, just released a new book with some fun news for all of us saving for retirement.
Bengen’s updated research shows that it’s safe to increase your withdrawal rate in retirement from 4% to 4.7%.
Bengen’s new book is called A Richer Retirement: Supercharging the 4% Rule to Spend More and Enjoy More.
Let’s dive in.
Coast FIRE Example 1: Clarke is 35-years-old and ready for a new job.
Clarke is 35-years-old and is ready for a career change.
His job at a prestigious law firm has taught him a lot and he’s made good money. But, the stress and the hours are starting to take a toll on his personal life and on his health.
He’s ready to pivot.
Because he was making good money, Clarke maxed out his 401(k) retirement plan for the past 8 years. He now has $400,000 saved up. He also currently adds $5,000 to his various retirement accounts each month.
His goal is to have $200,000 annually to spend in retirement.
Based on the above variables, Clarke’s Coast FIRE number is $559,009.
At his current saving rate, he will reach Coast FIRE in three years. That means that at the age of 38, he will no longer need to fund his retirement.
He could then pursue a lower paying, lower stress job without sacrificing his retirement years.
Note: Clarke’s FI number (magic retirement number) is significantly higher: $4,255,319.
That’s a big number and can seem intimidating. His Coast FIRE number is more encouraging to think about.
Yes, he’ll have to keep working to fund his current lifestyle. But, he can choose to work a lot less.
What if three years still seems too far away for Clarke?
Using the Coast FIRE calculator, Clarke learns that if he ups his retirement contributions from $5,000 per month to $8,000 per month, he will achieve Coast FIRE in two years.
That’s powerful information. If he boosts his saving rate even more, he can pivot even faster.
Armed with the knowledge of his Coast FIRE number, Clarke has a newfound motivation to stick it out at his current job for just a bit longer.

Coast FIRE Example 2: David is 40-years-old and worried about paying for college.
David had a kid about a year ago and is freaking out about paying for college. He knows that it’s important to prioritize his own retirement before prioritizing his kid’s college.
David has $300,000 saved for retirement. His goal is to spend $150,000 annually in retirement. He currently has $6,000 available to invest each month, whether that’s for retirement or college.
Let’s help David out by using the Coast FIRE calculator.
Plugging in these variables, we see that David’s Coast FIRE number is $588,029.
Notice how David’s Coast FIRE number is higher than Clarke’s, even though he plans to spend less in retirement. That’s because he has a shorter time horizon and less currently saved.
This is another reminder to start investing early and often.
Even so, David is in great shape for retirement. At his current pace, David is 5 years away from reaching Coast FIRE. His daughter will only be six-years-old at that point.
That means that David will still have 12 years to prioritize saving for his daughter’s college, all while knowing that his retirement is covered.
This knowledge makes David feel much better. He’s no longer worried about paying for his daughter’s college at the expense of saving for retirement.
Coast FIRE Example 3: Dorothy is 28-years-old and just paid off her student loans.
Dorothy is 28-years-old and is in the early stage of her career as a lobbyist in Washington D.C. She lives with 3 roommates outside of town and keeps her expenses very low.
Dorothy has her whole life ahead of her so hasn’t thought too much about the specifics of retirement.
But, she knows enough to think and talk money with her friends and family every once in a while.
In one of these conversations, she learned about Coast FIRE and was interested in calculating what her number is. Dorothy thought about how amazing it would be to pursue a life on her own terms without worrying about retirement.
Dorothy just finished paying off her student loans. Because she was focused on her loans, she currently has only $10,000 saved for retirement.
She now plans to roll the $5,000 per month she had been using for loan payments into her retirement account.
Because she was so far away from retirement, Dorothy thought it was best to error on the side of caution with her annual spending projections.
So, Dorothy estimated that she would need $250,000 annually in retirement, much more than both Clarke and David figured.
Based on the above, Dorothy’s Coast FIRE number is $435,153. She can achieve Coast FIRE by the age of 38!
Dorothy’s Coast FIRE number is significantly lower than Clarke’s and David’s, even though she plans to spend way more in retirement.
Of course, this is because she is getting started so early.
Knowing that she can fund her entire retirement in just 10 years, Dorothy makes it a priority to do so.
By the age of 38, she will be free to pursue any line of work she chooses without needing another dollar to fund her seemingly extravagant retirement.
That makes Dorothy very happy.
Use a Coast FIRE calculator to figure out your own number.
The above examples show how knowing your Coast FIRE number can be so liberating.
When you calculate how much you’ll need to retire, you may be surprised at how close you actually are.
If you’ve been avoiding making big life decisions because of anxiety about retirement, knowing your Coast FIRE number can be a huge help.
Clarke, David and Dorothy calculated their Coast FIRE numbers and were able to come up with manageable plans.
Each person is on track for a desirable retirement, all while creating options for themselves earlier in life.
Having options is a great thing.
Have you calculated your Coast FIRE number?
Were you surprised how close you actually are to achieving your retirement goals?
Let us know in the comments below.