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You are $197,066 short of Coast FIRE today. At 5.0% real over 30 years you would need $347,066 invested now for compounding alone to reach $1,500,000. Saving $25,000 a year, you can stop around age 45 and let the balance coast to 65.
Coast sooner: what to save each month
The calculator shows when you reach Coast FIRE at your current pace. To pick the age instead, enter it here. The answer is the level saving that brings your balance to the Coast FIRE number for that age, using the same inputs as above.
Saving about $2,127 a month ($25,521 a year) from now until 45, at 5.0% real, lets you stop at 45 and still reach $1,500,000 by 65.
What is Coast FIRE
Coast FIRE is the point where the money you already have invested will grow to your retirement number on its own. You will also see it written CoastFIRE, CoastFI or Coast FI; they all mean the same milestone, so a Coast FI calculator answers the same question. Reaching it does not mean you can stop working. It means you can stop saving for retirement, because compounding will finish the job, and your pay only has to cover the years between now and then. The full number, the portfolio that covers all your spending with no more work, is what the FIRE number calculator works out.
The formula is one compound-growth calculation run backwards: Coast FIRE number = retirement target ÷ (1 + real return) raised to the years until retirement. If you need $1.5 million at 65, expect a 5% real return, and you are 35, you need roughly $347,000 invested today. Its practical value is freedom: once you coast, a lower-paid job, a sabbatical or a career change is survivable rather than reckless. The answer is very sensitive to the return you assume. Over thirty years, 5% versus 7% is close to a factor of two.
Coast FIRE examples
Three households, all aiming to retire at 65 with a 4% withdrawal rate and a 5% real return. Social Security is entered in today's dollars and lowers the target.
| Household | Invested today | Retirement target | Coast FIRE number | Where they stand |
|---|---|---|---|---|
| Maya, 25, single, first job | $30,000 | $1,250,000 | $177,557 | Saving $15,000 a year, can stop at 38 |
| Sam and Jordan, 32, a couple saving together | $140,000 | $1,100,000 | $219,860 | Saving $25,000 a year, can stop at 35 |
| Lee, 40, single, mid-career | $420,000 | $950,000 | $280,538 | Already coasting, $139,462 ahead |
- Maya, 25 plans to spend $50,000 a year and leaves Social Security out, so the portfolio needs $1,250,000 at 65. With $30,000 invested, the Coast FIRE number is $177,557; saving $15,000 a year gets there around age 38.
- Sam and Jordan, 32 plan to spend $80,000 a year with $36,000 of Social Security, so the portfolio needs $1,100,000 at 65. With $140,000 invested, the Coast FIRE number is $219,860; saving $25,000 a year gets there around age 35.
- Lee, 40 plans to spend $60,000 a year with $22,000 of Social Security, so the portfolio needs $950,000 at 65. With $420,000 invested, Lee has already passed the $280,538 Coast FIRE number and could stop saving for retirement today.
Coast FIRE number by age
The same target, discounted to each starting age with the inputs above. Younger rows are smaller because they have more years of compounding left, not because retirement is cheaper.
| Age today | Years to retirement | Coast FIRE number |
|---|---|---|
| 25 | 40 | $213,069 |
| 30 | 35 | $271,935 |
| 35 | 30 | $347,066 |
| 40 | 25 | $442,954 |
| 45 | 20 | $565,334 |
| 50 | 15 | $721,526 |
| 55 | 10 | $920,870 |
| 60 | 5 | $1,175,289 |
A standalone version with its own inputs is the Coast FIRE by age table, and each age from 20 to 50 has its own page with other spending levels, returns and the time it takes: Coast FIRE number by age. To see where other households your age actually stand, compare your row with the average 401(k) balance by age and retirement savings by age.
Coast FIRE number by annual spending
Your retirement target comes from a safe withdrawal rate. Under the 4% rule the portfolio has to be 25 times the spending it funds, so every $10,000 of yearly spending adds $250,000 to the target. Here is the Coast FIRE number for five budgets, retiring at 65 with a 5% real return:
| Annual spending | Target at 65 | At 30 | At 35 | At 40 | At 45 |
|---|---|---|---|---|---|
| $40,000 | $1,000,000 | $181,290 | $231,377 | $295,303 | $376,889 |
| $50,000 | $1,250,000 | $226,613 | $289,222 | $369,128 | $471,112 |
| $60,000 | $1,500,000 | $271,935 | $347,066 | $442,954 | $565,334 |
| $80,000 | $2,000,000 | $362,581 | $462,755 | $590,606 | $753,779 |
| $100,000 | $2,500,000 | $453,226 | $578,444 | $738,257 | $942,224 |
Spending is the lever you control most directly. Planning to retire on $50,000 instead of $60,000 lowers the Coast FIRE number at 35 from $347,066 to $289,222. A more cautious safe withdrawal rate works the other way: at 3.5%, the target is about 28.6 times spending instead of 25.
How the return you assume changes the number
The return is the input that moves the answer most. Here is your Coast FIRE number for the same $1,500,000 target and 30 years to retirement at four real returns.
| Real return | Coast FIRE number | Versus your current setting |
|---|---|---|
| 4% | $462,478 | +$115,412 |
| 5% | $347,066 | Your setting |
| 6% | $261,165 | −$85,901 |
| 7% | $197,051 | −$150,015 |
A real return is the return after inflation, which is why every figure on this page is in today's dollars. If you think in nominal returns, take inflation off first: 7% nominal with 2.5% inflation is about 4.4% real. Entering a nominal return here would overstate how far your money grows and make Coast FIRE look closer than it is.
Coast FIRE and market risk: would coasting have worked?
A Coast FIRE number assumes the same return every year. Markets do not deliver that, so we ran the number through 1,000 simulated 30-year markets: a 5% average real return with 15% yearly swings, roughly a stock-heavy portfolio. Each row starts a 35-year-old at the Coast number for a planning return, saves nothing more, and checks whether the balance reaches the $1,500,000 target at 65.
| Planning return | Coast number at 35 | Paths that reached the target | Median balance at 65 | Bad case (10th percentile) |
|---|---|---|---|---|
| 5% real | $347,066 | 35% | $1,075,955 | $389,575 |
| 4% real | $462,478 | 48% | $1,433,748 | $519,123 |
| 3% real | $617,980 | 62% | $1,915,827 | $693,671 |
Coasting on the number set at the full 5% average reached the target in only 35% of paths. Volatility is why: losses cost more than equal gains earn back, so a portfolio that averages 5% a year compounds at less than 5%. Setting the number with a 4% planning return lifted the hit rate to 48%, and 3% to 62%. Even then the bad cases fall well short, which is why reaching Coast FIRE is a reason to re-check every year, not to stop looking. To see a single bad sequence play out, use the sequence of returns calculator; the Monte Carlo retirement calculator runs your own figures through 1,000 paths.
Year by year
Your balance each year if you keep saving $25,000 a year until the coast point and then stop, next to the balance if you stopped saving today.
Show the year-by-year table
| Age | Saving until you coast | Stop saving today |
|---|---|---|
| 35 | $150,000 | $150,000 |
| 36 | $182,500 | $157,500 |
| 37 | $216,625 | $165,375 |
| 38 | $252,456 | $173,644 |
| 39 | $290,079 | $182,326 |
| 40 | $329,583 | $191,442 |
| 41 | $371,062 | $201,014 |
| 42 | $414,615 | $211,065 |
| 43 | $460,346 | $221,618 |
| 44 | $508,363 | $232,699 |
| 45 | $558,782 | $244,334 |
| 46 | $611,721 | $256,551 |
| 47 | $642,307 | $269,378 |
| 48 | $674,422 | $282,847 |
| 49 | $708,143 | $296,990 |
| 50 | $743,550 | $311,839 |
| 51 | $780,728 | $327,431 |
| 52 | $819,764 | $343,803 |
| 53 | $860,752 | $360,993 |
| 54 | $903,790 | $379,043 |
| 55 | $948,979 | $397,995 |
| 56 | $996,428 | $417,894 |
| 57 | $1,046,250 | $438,789 |
| 58 | $1,098,562 | $460,729 |
| 59 | $1,153,490 | $483,765 |
| 60 | $1,211,165 | $507,953 |
| 61 | $1,271,723 | $533,351 |
| 62 | $1,335,309 | $560,018 |
| 63 | $1,402,075 | $588,019 |
| 64 | $1,472,179 | $617,420 |
| 65 | $1,545,787 | $648,291 |
Coast FIRE with Social Security or a pension
Your portfolio only has to fund the spending that other income does not cover. If you plan to spend $60,000 a year and expect $20,000 from Social Security, the portfolio target at a 4% withdrawal rate falls from $1,500,000 to $1,000,000. At 35 with a 5% real return, the Coast FIRE number falls with it, from about $347,000 to about $231,000. Enter the benefit in today's dollars; your estimate is on your my Social Security account. If benefits start several years after you retire, the portfolio has to cover the full spend until then, so treat the result as optimistic by that gap.
Coast FIRE for couples
Run the household as one plan. Add both partners' invested balances, use your combined retirement spending, and enter the combined Social Security or pension income. Use the age of the partner who will stop working first, because that is when withdrawals start. If one partner keeps saving after the other coasts, enter the saving that continues until the coast point.
What happens after you reach Coast FIRE
Your retirement savings are on track, but your living costs are not covered yet, so you still need an income until you retire. What changes is how much that income has to be. People who reach Coast FIRE often:
- Move to work they prefer over work that pays most: a lower-stress role, part-time hours, freelancing or a career change. These are sometimes called Coast FIRE jobs.
- Take a sabbatical, or time off for family, without derailing retirement.
- Keep contributing enough to collect an employer 401(k) match, which is free money even after you coast.
- Re-run the numbers once a year. A weak decade of returns can push you back below the line, and a few years of extra saving then puts you back on track.
Is Coast FIRE realistic?
It is more reachable than full FIRE because you only have to save the first part of the number; time does the rest. In the Fed's 2025 survey about 1 in 9 households aged 25 to 64 had already passed the Coast FIRE number for a $1 million target: how many Americans have reached Coast FIRE. That is also its weak point. The plan leans on decades of returns you cannot see yet, so it is worth knowing what can break it:
- Returns below your assumption. The table above shows how far the number moves between 4% and 7% real.
- A bad sequence near retirement. A crash in the years just before or after you retire does more damage than the same crash early on; see the sequence of returns calculator.
- Spending that grows. The target assumes today's retirement budget, adjusted only for inflation. Children, housing or health costs can change it.
- Health insurance before Medicare. Retiring before 65 means paying for coverage yourself; the health insurance guide covers the options.
Planning with a slightly lower return than you expect, or saving a little past the coast point, builds in a margin that covers most of these.
How to reach Coast FIRE faster
Each lever below changes one input in the formula. For a 35-year-old aiming at $60,000 a year from 65 at a 5% real return, the Coast FIRE number is $347,066.
- Raise your savings rate now. Money saved in your 20s and 30s has the most years to compound, so a higher savings rate early shortens the wait the most. The savings rate calculator shows the effect on the years to financial independence.
- Take the full employer match. A 401(k) match is an instant return on what you contribute, before any market growth.
- Cut investment fees. A 1% fee turns a 5% real return into roughly 4%, which raises the Coast number to $462,478. The investment fee calculator shows the cost in dollars.
- Lower the retirement budget. Every $10,000 less spending in retirement takes $250,000 off the target and $57,844 off today's Coast number.
- Retire a little later. Each extra year of compounding cuts the Coast number by about 5% at a 5% return: retiring at 67 instead of 65 lowers it to $314,799.
- Count other income. Social Security, a pension or rental income lowers the portfolio target, as the Social Security section above shows.
- Use tax-advantaged accounts. Growth inside a 401(k), IRA, Roth IRA or HSA is not taxed each year, so more of the return compounds.
Coast FIRE vs FIRE vs Barista FIRE
| Milestone | What you stop | What pays today's bills | Calculator |
|---|---|---|---|
| Coast FIRE | Saving for retirement | Your job, full or part time | This page |
| Barista FIRE | Full-time work | Part-time pay plus portfolio withdrawals | Barista FIRE calculator |
| FIRE | Working at all | Portfolio withdrawals alone | FIRE calculator |
Coast FIRE usually comes first, often in your 30s or 40s, because it needs the smallest balance. Lean FIRE and Fat FIRE are the same full-FIRE milestone at a smaller or larger budget: the Lean FIRE calculator and the Fat FIRE calculator size them.
Coast FIRE and your 401(k)
Money in a 401(k), 403(b) or IRA counts toward your Coast FIRE number, and so does a taxable brokerage account. Coasting does not mean leaving your plan: many people keep contributing up to the employer match. Two details matter more if you also plan to retire early:
- Taxes. Traditional 401(k) and IRA withdrawals are taxed as income, so a target built from pre-tax balances needs to cover the tax as well. The retirement tax calculator estimates it.
- Access before 59½. Withdrawals before 59½ usually carry a 10% penalty. The Rule of 55 calculator, the 72(t) calculator and the Roth conversion ladder calculator cover the three common ways around it.
How it works
Spending minus other income, divided by the withdrawal rate, is the retirement target (4% is 25 times). That target is discounted back to today at the real return. With the figures above, $1,500,000 over 30 years at 5.0% is $347,066 today. The stop-saving age solves for the first point at which your balance, left alone from then on, still grows to the target by 65: age 45 with the inputs above.
Coast FIRE is one of several milestones. The FIRE number calculator keeps saving until the whole number is reached, and the Barista FIRE calculator sizes a plan where part-time pay covers part of spending.
Methodology and sources
- Retirement target: annual spending in today's dollars, minus Social Security or pension income, divided by the withdrawal rate (4.0% here).
- Coast FIRE number: the target divided by (1 + real return) raised to the years until retirement. Contributions are made at the end of each year.
- Withdrawal rate: the 4% default comes from William Bengen's 1994 study of historical US returns ("Determining Withdrawal Rates Using Historical Data", Journal of Financial Planning) and the 1998 Trinity study by Cooley, Hubbard and Walz. Both looked at 30-year retirements, so longer ones often use 3.25% to 3.5%.
- Social Security: your own estimate from the Social Security Administration, entered in today's dollars.
One constant real return, no fees, and a withdrawal rate that holds for your horizon. Markets do not deliver a constant return: see the Monte Carlo retirement calculator for a range of outcomes. A 1% fee is a large change over decades; the fee calculator sizes it. Spending rules that flex once you are drawing are the Guyton-Klinger calculator and the Vanguard dynamic spending calculator. How we build and check every calculator is on the methodology page.
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