Coast FIRE Calculator
How much you need invested today to coast to financial independence
Enter your numbers and see if your savings can already coast to retirement
Free · No sign-up · Updates as you typeCoast FIRE is the point where the money you have already invested is big enough to reach your retirement target on its own, with nothing added. You still work to pay today's bills, but you can stop saving for retirement.
In whole years, e.g. 30.
When the money has to be ready, e.g. 60.
$
Shares, funds, ETFs and pensions, e.g. 100,000.
$
Optional. Put 0 if you have stopped adding money.
e.g. 5 for 5% a year above inflation.
$
In today's prices, e.g. 40,000 a year.
e.g. 4 for the 4% rule.
What you need invested today to land on $1,000,000 at age 60, adding nothing more
$231,377
Not there yet, you are 43% of the way
You are $131,377 short of the amount that would coast on its own.
In plain terms: spending $40,000 a year and taking out 4.0% of the pot each year means you need $1,000,000 by age 60. At 5.0% a year, money multiplies about 4.3 times over 30 years, so you only need $231,377 invested today. You have $100,000, so you are $131,377 short. Left alone, what you hold grows to $432,194.
All the figures above are in today's money. You gave a return after inflation, so the target is what your spending costs at today's prices. The balance you actually see at retirement will be a larger number that buys the same things.Pot you need at retirement
$1,000,000
What you hold grows to, adding nothing
$432,194
Still short today
$131,377
How far along you are
43%
When do you reach it?
Keep investing $1,000 a month and you reach Coast FIRE at about age 46, roughly 15.8 years from now. From that day you could stop saving for retirement and let the pot finish the job on its own.
How much the return you assume changes it
The real return is the biggest guess in this whole calculation, so it pays to see the spread. Same spending, same ages, different assumed returns.
| Real return a year | You need invested today | With what you have now |
|---|---|---|
| 3.0% | $411,987 | $311,987 short |
| 4.0% | $308,319 | $208,319 short |
| 5.0% (yours) | $231,377 | $131,377 short |
| 6.0% | $174,110 | $74,110 short |
| 7.0% | $131,367 | $31,367 short |
The coast number climbs every year, because fewer years of growth are left to do the work. The row where your pot catches it is the year you become Coast FIRE.
| Age | Coast number at that age | Your pot |
|---|---|---|
| 30 | $231,377 | $100,000 |
| 31 | $242,946 | $117,273 |
| 32 | $255,094 | $135,409 |
| 33 | $267,848 | $154,452 |
| 34 | $281,241 | $174,447 |
| 35 | $295,303 | $195,442 |
| 36 | $310,068 | $217,487 |
| 37 | $325,571 | $240,633 |
| 38 | $341,850 | $264,938 |
| 39 | $358,942 | $290,457 |
| 40 | $376,889 | $317,253 |
| 41 | $395,734 | $345,388 |
| 42 | $415,521 | $374,930 |
| 43 | $436,297 | $405,949 |
| 44 | $458,112 | $438,519 |
| 45 | $481,017 | $472,717 |
| 46 | $505,068 | $508,626 |
| 47 | $530,321 | $546,330 |
| 48 | $556,837 | $585,919 |
| 49 | $584,679 | $627,487 |
| 50 | $613,913 | $671,134 |
| 51 | $644,609 | $716,964 |
| 52 | $676,839 | $765,084 |
| 53 | $710,681 | $815,611 |
| 54 | $746,215 | $868,664 |
| 55 | $783,526 | $924,370 |
| 56 | $822,702 | $982,861 |
| 57 | $863,838 | $1,044,277 |
| 58 | $907,029 | $1,108,763 |
| 59 | $952,381 | $1,176,474 |
| 60 | $1,000,000 | $1,247,570 |
Insight: Coast FIRE is reached the moment your invested balance is large enough that compound growth alone will reach your full FIRE number by retirement. After that point you only need to cover your current living costs from income, your investments coast the rest of the way. These figures are projections based on your assumptions and are not guarantees.
Coast FIRE is a milestone on the path to financial independence. It is the point where your existing investments are large enough that, left untouched and with no new contributions, compound growth alone will reach your full retirement target by your chosen retirement age. This calculator works out that Coast FIRE number and compares it with what you already have invested.
Coast Number = FIRE Number / (1 + r)^years
The monthly amount you invest is deliberately kept out of that formula. Coast FIRE is by definition what your money can do with nothing added, so contributions only answer the second question on the page, how soon you get there.
Step 1: Enter your current age and the age at which you plan to retire. The gap between them is your compounding horizon.
Step 2: Enter what you already have invested and, if you are still adding money, how much you invest each month. Then set the yearly return you expect after inflation.
Step 3: Enter your desired annual retirement spending and your safe withdrawal rate. Together these set your full FIRE number.
Step 4: Nothing to click. The answer updates as you type, so change the return or the retirement age and watch the coast number move.
What Is Coast FIRE?
Coast FIRE is a stage on the journey to financial independence, retire early (FIRE). You reach Coast FIRE when you have enough money already invested that, even if you never contribute another dollar, compound growth alone will carry your portfolio to your full financial independence number by the time you want to retire. At that point your retirement is, in a sense, already funded, you simply need to let it grow.
What makes Coast FIRE appealing is the freedom it offers before full retirement. Once you have hit your Coast FIRE number, you no longer need to save aggressively for retirement; you only need enough income to cover your present-day living expenses. That can mean switching to a lower-paying but more enjoyable job, working fewer hours, taking a career break, or starting a business, because the heavy lifting of retirement saving is already done.
The Coast FIRE Formula
Coast Number = FIRE Number / (1 + r)^years
The calculation has two steps. First, work out your full FIRE number by dividing your desired annual retirement spending by your safe withdrawal rate. With the widely cited 4% rule, that means multiplying your annual spending by 25, for example, $40,000 of yearly spending implies a FIRE number of $1,000,000. The withdrawal rate is your own assumption about how much of your portfolio you can sustainably draw down each year.
Second, discount that FIRE number back to today using your expected real return and the number of years until retirement. Because you are working in today's dollars, the return you use should be a real return, the nominal return minus inflation. The result is your Coast FIRE number: the amount that, invested today and left to compound, grows to your full FIRE number by retirement. If you compare it against the related compound interest and SIP tools, you can see how regular contributions would accelerate reaching that figure.
Coast FIRE vs Barista, Lean and Fat FIRE
The FIRE movement has developed several variations that describe different lifestyles and risk appetites. Coast FIRE, as described above, means your invested assets will grow to your target without further saving, while you keep working to cover current expenses. Barista FIRE is closely related: you have enough invested to cover part of your expenses, and you take a part-time or lower-stress job, often one that provides health benefits, to bridge the rest until your investments are fully drawn upon.
Lean FIRE describes reaching financial independence with a modest, frugal budget, requiring a smaller portfolio because annual spending is low. Fat FIRE is the opposite, a larger portfolio that supports a more comfortable or even luxurious lifestyle with higher annual spending. The right target depends entirely on your own spending plans and values. You can model the part-time bridge scenario with the Barista FIRE calculator to see how Coast and Barista strategies fit together.
Why Coast FIRE Matters
Coast FIRE highlights one of the most powerful ideas in personal finance: the earlier you invest, the more compounding does the work for you. Money invested in your twenties has decades to grow, so a relatively modest Coast FIRE number early in life can become a large portfolio by traditional retirement age. Reaching Coast FIRE can reduce financial anxiety and widen your choices, since you no longer have to optimise every decision around maximising savings. It is a planning milestone rather than a finish line, and the numbers should be revisited as your circumstances, returns, and spending expectations change.
Frequently Asked Questions About the Coast FIRE Calculator
Coast FIRE is the point at which you have enough already invested that, with no further contributions, compound growth alone will carry your portfolio to your full financial independence number by your target retirement age. Once you reach your Coast FIRE number, you still need to cover your current living costs from income, but you no longer need to save for retirement, your existing investments will coast the rest of the way.
Use a real return, the return after subtracting inflation, because your future spending number is in today's dollars. A common assumption for a diversified stock-heavy portfolio is a real return of around 5% to 7%, derived from long-run historical equity returns of roughly 7% to 10% nominal minus 2% to 3% inflation. More conservative planners use 4% to 5%. The assumption is uncertain, so it is wise to test several rates rather than relying on a single optimistic figure.
Not by waiting, and this catches people out. If you add nothing, your pot grows at your assumed real return, but the Coast FIRE number grows at exactly the same rate, because every year that passes leaves one less year of compounding to do the work. The two rise in step, so the gap never closes on its own. Only fresh contributions, a later retirement age, or lower planned spending will close it.
Coast FIRE relies on assumptions about future investment returns, inflation, your retirement age, and your safe withdrawal rate, none of which are guaranteed. A long stretch of poor market returns, higher-than-expected inflation, or earlier retirement can all leave you short. Coast FIRE is best treated as a planning milestone and a directional guide rather than a certainty. Revisiting the numbers regularly and keeping a margin of safety makes the approach more robust.
Coast FIRE and the Wider FIRE Toolkit
Coast FIRE works best as one input among several. Because the whole approach rests on compound growth doing the heavy lifting, it is worth seeing exactly how a balance grows over time with the compound interest calculator and, if you are still contributing, how regular monthly investments accelerate your progress with the SIP calculator.
If you would rather keep working part-time once your portfolio is large enough to cover some of your expenses, the Barista FIRE calculator shows how a smaller bridge income changes the picture. Used together, these tools help you compare different paths to financial independence and choose the one that best fits your goals and risk tolerance.
Track Your Progress Toward Financial Independence
Knowing your Coast FIRE number is the first step. With Worthmap, you can track your real-time net worth, monitor investments across currencies, and see how close you are to financial independence.
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