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Coast FIRE Calculator
Find your Coast FIRE number — the portfolio that, left alone, compounds to full financial independence by your retirement age. See whether you've already hit it, and if not, exactly what closes the gap. Free, instant, and nothing to sign up for.
Your age today, in whole years.
The age at which you'd like your portfolio to fully fund retirement.
$
Stocks, bonds, funds, retirement accounts — money that is invested and growing.$
The yearly spending your portfolio would need to cover, in today's money.%
Nominal, before inflation. 7% is a common long-run stock estimate.%
The 4% rule: the share of your portfolio you withdraw each year.All amounts above are in this currency.
Enter your current age, target retirement age and annual expenses (with a withdrawal rate above zero) to see your Coast FIRE number.
Assumes a constant nominal return with no further contributions (the monthly figure compounds monthly) and expenses in today’s money. Estimates only — not financial advice.
Typing these numbers by hand? Guaca tracks them for you — accounts, investments and exchange rates update automatically, every day.
Start freeWhat is Coast FIRE?
Coast FIRE is the point where you have saved enough, early enough, that compounding alone finishes the job. Once your portfolio crosses that threshold, it will grow to your full FIRE number by your target retirement age with zero further contributions — you can stop saving for retirement entirely and simply coast. You still work, but only to cover today’s expenses; the retirement problem is already solved, it just needs a couple of decades to cook. That is a fundamentally different milestone from full FIRE: instead of asking “when can I quit?”, Coast FIRE asks “when does saving become optional?” — and for people who start investing in their 20s or 30s, the answer arrives startlingly early.
The math: your FIRE number, discounted back to today
Start from your full FIRE number — annual expenses divided by your safe withdrawal rate, the classic 25× at 4% (our FIRE calculator covers that side in depth). Coast FIRE then runs compounding in reverse: instead of asking what a portfolio grows into, it asks what has to exist today to grow into the FIRE number by retirement age.
Coast FIRE number = FIRE number ÷ (1 + return)years
Say you spend $40,000 a year, so your FIRE number at 4% is $1,000,000. If you are 30, plan to retire at 65, and expect 7% a year, the divisor is 1.07³⁵ ≈ 10.7 — your Coast FIRE number is roughly $94,000. Have that invested at 30 and the remaining $906,000 is manufactured entirely by time and compounding.
The exponent is what makes the result so dramatic: every year of runway divides the target again. The same math that makes early contributions so powerful in our compound interest calculator works here in reverse — a 25-year-old needs a far smaller Coast number than a 45-year-old with identical spending, not because of anything they did, but because their money has twenty more doublings-worth of time ahead of it.
It changes your career before it changes your retirement
Full FIRE changes your life on the day you quit. Coast FIRE changes it the day you cross the number — often decades earlier — because from that point on, work only has to cover your current expenses. The 20–40% of income that was flowing into retirement accounts is suddenly optional, and so is the salary that funded it. That opens doors long before any retirement party: downshifting to a four-day week, taking the lower-paid job you would actually enjoy, a sabbatical between chapters, moving somewhere cheaper, or turning a passion project into the day job even if it pays half as much. The psychological shift is just as real — market crashes stop threatening your retirement date, because the plan never depended on your next contribution anyway.
The catch
Coast FIRE leans on one assumption harder than any other FIRE variant: a single average return, held for decades, with no plan B. Three things deserve respect before you act on the number. First, inflation — your expenses are in today’s money, so a nominal 7% overstates the case; using a real return like 5% keeps both sides of the equation honest. Second, healthcare: downshifting careers often means downgrading employer coverage, and for Americans years away from Medicare that can be the single biggest line item the plan forgot. Third, sequence riskdoesn’t vanish just because you stopped contributing — a weak decade early in the coast phase leaves less capital to compound, and with no contributions flowing in, nothing buys the dip for you. A margin above the bare Coast number, or a willingness to resume saving after bad years, covers most of it.
Coast FIRE vs full FIRE vs Barista FIRE
Full FIRE means the portfolio covers everything, today — you hold 25× your annual expenses and work is entirely optional. It is the biggest target and the longest grind, but the only variant where no paycheck is ever needed again.
Coast FIREis the smallest target: retirement is funded, but you keep working for current expenses until traditional retirement age. You give up early retirement itself in exchange for reaching “the saving is done” decades sooner.
Barista FIRE sits in between: you quit the main career early and let part-time income cover part of your spending while the portfolio covers the rest. It needs more than the Coast number — withdrawals start while the money should still be compounding — but far less than full FIRE. Many people chain them: hit Coast, keep saving anyway toward a concrete savings goal, then switch to Barista once the cushion allows it. And once the numbers get serious, pressure-test the whole plan with the retirement calculator for the USA, which models the withdrawal phase this page takes as given.
This page is educational — it is not financial, tax or investment advice.
Frequently asked questions
Is Coast FIRE realistic?
More realistic than full FIRE, for most people — that is precisely its appeal. Full FIRE demands you accumulate 25× your annual expenses; Coast FIRE only asks for that amount discounted back by decades of compounding, which can be a quarter or a fifth of the full number if you start in your 20s or 30s. The realism caveat is the assumption load: you are trusting a single average return to hold for 20–40 years, trusting your future spending estimate, and trusting yourself to genuinely leave the portfolio alone. A conservative real return and an honest expense number make the answer trustworthy; an optimistic 10% nominal makes it a fantasy.
What return should I assume?
Use a real (inflation-adjusted) return, because your annual expenses are in today's money and the horizon is long enough for inflation to matter enormously. US stocks have returned roughly 9–10% nominal over the last century, but about 6–7% after inflation — and a diversified portfolio with bonds lands lower. Something like 5% real is a common, defensible planning assumption; 7% nominal only works if you also inflate your future expenses. The longer your coast period, the more a small change in this one input swings the result, so try a pessimistic and an optimistic case rather than betting on one number.
Do I include my house in the portfolio?
No. The Coast FIRE math assumes the portfolio compounds untouched and is then drawn down at your withdrawal rate — you cannot withdraw 4% of a house each year to pay for groceries. Where a paid-off home does enter the picture is on the expense side: no rent or mortgage in retirement means lower annual expenses, which shrinks the FIRE number and therefore the Coast number too. Count home equity only if you have a concrete plan to sell or downsize and invest the difference.
What happens if I keep contributing anyway?
You retire earlier, or with a bigger cushion — coasting is a floor, not a ceiling. Hitting your Coast FIRE number means contributions are no longer required to retire on schedule; it does not mean they stop helping. Every dollar you keep investing either pulls the full-FIRE date forward or raises the portfolio you arrive with, which is valuable insurance against below-average returns. Many people treat Coast FIRE as the point where saving becomes optional and pressure-free rather than the point where it ends.
What is the difference between Coast FIRE and Barista FIRE?
Coast FIRE is about contributions; Barista FIRE is about withdrawals. Once you hit Coast FIRE you stop adding to the portfolio but keep working full income to cover current expenses — the portfolio is not touched until traditional retirement age. Barista FIRE goes a step further: you quit the main career early and start partially living off the portfolio, with part-time work (the stereotypical coffee-shop job with health benefits) covering the rest. Barista FIRE therefore needs a bigger portfolio than coasting, because withdrawals begin while the money is still supposed to be compounding.
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