Coast FIRE Calculator
Last verified · Methodology
Find the amount you need invested today so compounding alone carries you to financial independence. Adjust your age, spending target, and return assumptions to see exactly when you can stop saving for retirement.
Your numbers
Retirement accounts plus taxable brokerage. Exclude home equity and cash.
Set to zero to see pure coasting with no new money.
In today's dollars. The calculator adjusts for inflation.
Real return used in the math: 3.88%
You are 19% of the way to Coast FIRE
$320,332 to go
At $2,000 per month you reach Coast FIRE at age 49, in 19 years. After that you can stop saving entirely.
Your Coast FIRE number
$395,332
Needed invested today at age 30
Your full FIRE number
$1,500,000
$60,000 at 4% withdrawal
Balance vs Coast FIRE target
The dashed line rises because waiting costs you compounding. Where the green line crosses it, you are Coast FIRE.
Coast FIRE number by age
| Age | Coast FIRE number | Years of compounding left |
|---|---|---|
| 25 | $326,760 | 40 |
| 30 | $395,332 | 35 |
| 35 | $478,294 | 30 |
| 40 | $578,665 | 25 |
| 45 | $700,100 | 20 |
| 50 | $847,019 | 15 |
| 55 | $1,024,768 | 10 |
| 60 | $1,239,820 | 5 |
Based on $60,000 annual spending, a 4% withdrawal rate, retirement at 65, and a 3.88% real return.
What is Coast FIRE?
Coast FIRE is the moment your retirement stops needing your paycheck. You have enough invested that ordinary compound growth, with no further contributions, will reach your full financial independence number by the age you want to retire. From that point forward you only need to earn enough to cover current living costs.
It is the first real milestone on the path to financial independence, and it usually arrives far earlier than people expect. A 30 year old with roughly $380,000 invested and a plan to retire at 65 has already funded retirement, even though the account is nowhere near the $1.5 million that retirement will actually require. The remaining $1.1 million comes from time, not from saving.
The practical effect is optionality rather than freedom from work. People who reach Coast FIRE commonly move to lower-paying work they prefer, cut back to part time, take a sabbatical, or accept the risk of starting something of their own. The retirement account is no longer a reason to stay in a job.
How to calculate your Coast FIRE number
The calculation has two steps.
Step 1: find your full FIRE number
Divide the annual spending you want in retirement by your safe withdrawal rate. The classic figure is 4%, which is where the common shorthand of 25 times annual spending comes from.
$60,000 ÷ 0.04 = $1,500,000
Step 2: discount it back to today
Your Coast FIRE number is the present value of that FIRE number, discounted at your expected real return over the years remaining until retirement.
r = real annual return, n = years until retirement
$1,500,000 ÷ (1.04)35 = $380,142
The single most important input is r, and it must be a real return, meaning after inflation. Using a nominal 10% instead of a real 7% understates your Coast FIRE number by more than half over a 35 year horizon. The calculator above takes your nominal return and your inflation assumption separately and converts them with the Fisher equation, so 7% nominal at 3% inflation produces 3.88% real rather than a rounded 4%.
Coast FIRE vs Barista FIRE vs Lean FIRE vs Fat FIRE
These four terms describe different destinations, and they get mixed up constantly. Coast FIRE is about timing. The other three are about the size of the number.
| Type | What it means | Still working? |
|---|---|---|
| Coast FIRE | Retirement is fully funded by existing investments. You cover only current expenses. | Yes, full time, but with no retirement saving required |
| Barista FIRE | Investments cover part of your expenses. A lower-stress job, often part time and often chosen for health insurance, covers the rest. | Yes, part time or lower paid |
| Lean FIRE | Full financial independence on a minimal budget, typically $25,000 to $40,000 per year. | No |
| Fat FIRE | Full financial independence on a generous budget, typically $100,000 or more per year. | No |
The distinction that matters most: Coast FIRE and Barista FIRE both assume you keep earning. Lean and Fat FIRE assume you have stopped. Someone can be Coast FIRE toward a Fat FIRE target, or Barista FIRE on a Lean FIRE budget. They are separate axes, not a single ladder.
What Coast FIRE does not solve
Coast FIRE is a genuinely useful checkpoint, but it is one calculation applied to a multi-decade outcome, and it hides a few real problems.
- Sequence of returns risk. A poor first decade can put you back below the line. The math assumes a smooth average return that no real portfolio ever delivers.
- The balance has to stay untouched. Coast FIRE assumes zero withdrawals for the entire remaining period. A job loss that forces an early withdrawal resets the clock.
- Health insurance is not in the number. For US early retirees this is often the single largest unplanned expense between leaving work and Medicare eligibility at 65.
- Spending estimates drift. The annual spending figure you pick at 30 is rarely the one you need at 65. Children, care for parents, and housing changes all move it.
The reasonable way to use it: recalculate once a year, keep contributing when you comfortably can, and treat crossing the line as permission to take more career risk rather than permission to stop planning.
If the number looks far away
If the number above looks far away, the two levers that move it most are your target retirement age and your current invested balance. Model the full picture with the retirement calculator, check how employer matching accelerates the balance with the 401(k) calculator, or see what a fixed monthly contribution becomes over decades with the compound interest calculator. The 4% rule explains where the withdrawal rate assumption comes from.
Coast FIRE is the point at which the money you already have invested will grow into your full financial independence number by your target retirement age without any further contributions. You are still working, but only to cover today's living expenses. Retirement is already funded by compounding. It is the earliest milestone on the FIRE path and usually arrives 10 to 20 years before full financial independence.
Two steps. First find your full FIRE number by dividing your desired annual retirement spending by your safe withdrawal rate, so $60,000 divided by 4% gives $1,500,000. Then discount that back to today using your expected real return and the years until retirement: Coast FIRE number equals FIRE number divided by (1 + real return) raised to the power of years remaining. At age 30 retiring at 65 with a 4% real return, $1,500,000 divided by 1.04 to the power of 35 gives roughly $380,000.
It depends on your age, target spending, and assumed return, which is why the calculator above asks for all three. As a reference point, using $60,000 in annual retirement spending, a 4% withdrawal rate, retirement at 65, and a 4% real return: at 25 you need about $312,000, at 30 about $380,000, at 35 about $462,000, at 40 about $562,000, and at 50 about $832,000. Waiting is expensive because you give up years of compounding.
Coast FIRE retirement is not retirement at all in the traditional sense. You keep working, but the psychological and financial pressure changes completely. Every dollar you earn goes to current living costs rather than to a retirement shortfall. Many people who hit Coast FIRE switch to lower-paying work they enjoy more, drop to part time, take career breaks, or start a business, because the retirement account no longer needs feeding.
You reach Coast FIRE the moment your invested balance crosses the Coast FIRE line for your age. The calculator above shows the crossover point given your current contributions. Two things pull that date closer: investing more now, and being willing to retire later. Extending your target retirement age by five years can reduce the required Coast FIRE number by 20% or more, because compounding gets five extra years to do the work.
Coast FIRE means your retirement is fully funded by existing investments and you work only to cover current expenses at whatever income level that requires. Barista FIRE means you have enough invested to cover part of your expenses, so you take a lower-stress job, often part time and often chosen for health insurance, to cover the rest. Coast FIRE is about the retirement account being finished. Barista FIRE is about the paycheck being smaller. Many people pass through Coast FIRE on the way to Barista FIRE.
Use a real return, meaning after inflation. The S&P 500 has returned roughly 10% nominally over the long run and about 7% after inflation, but a Coast FIRE plan that only works at 7% real is fragile. Most careful planners use 4% to 5% real for a stock-heavy portfolio. The calculator above takes your nominal return and inflation assumption separately and derives the real return with the Fisher equation, so a 7% nominal return at 3% inflation gives 3.88% real, not 4.00%.
The main risk is that Coast FIRE is a single point-in-time calculation applied to a 30 year outcome. A decade of poor returns early on can put you behind the line again, and the math assumes you never touch the balance. It is safest to treat Coast FIRE as a checkpoint rather than a finish line: recalculate annually, keep contributing when you can, and avoid withdrawing from retirement accounts. Health insurance costs and long-term care are the other common gaps that a pure Coast FIRE number does not cover.
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