Coast FIRE Calculator

Find the amount you would need today for compounding to reach a retirement target under your chosen return assumption.

Under a constant 7% return assumption, reaching $1,500,000 by age 65 from age 30 would require about $140,494 today with no further contributions. That is the modeled Coast FIRE number for this scenario. Adjust the target, ages or return to model your own path.

Your plan

Calculations run in your browser. Inputs are not stored.

The age by which you want the target reached.

$

Enter the portfolio you want at retirement in future dollars. If your goal is in today’s purchasing power, convert it to a future-dollar target first; see the inflation example below.

%

Presets are illustrative scenario inputs, not return forecasts. Because the Coast FIRE number is highly sensitive to the assumed return, test lower and higher rates.

Coast FIRE number — modeled amount today
$140,494

35 years of runway to age 65

Target at retirement$1,500,000
Compounding runway35 years
Expected annual return7%

This threshold assumes the selected return every year and no further contributions. Real returns vary, and the result is not a guarantee of retirement readiness.

PortfolioRetirement target

Show yearly breakdown
YearPortfolioRetirement target

The default 7% is an illustrative nominal annual return before inflation, not a forecast or a historical real return. This calculator has no inflation toggle. Pair the nominal return with a future-dollar target. See a worked example converting a today’s-dollar goal →

How this calculation works

The Coast FIRE number

Your Coast FIRE number is the present value of your retirement target, discounted at your assumed return:

Coast FIRE number = target ÷ (1 + annual return)years

For a $1,500,000 target at 65 with 35 years of runway at 7%, that is $1,500,000 ÷ 1.0735 ≈ $140,494.

How the target varies with your age

Current ageYears to 65Coast FIRE number
3035~$140,494
4025~$276,374
5015~$543,669

All rows assume a $1,500,000 target and 7% annual return. The earlier you start, the less you need — that is the pure math of compounding.

Return sensitivity (30 years of runway)

Assumed returnCoast FIRE number
5%~$347,066
6%~$261,165
7%~$197,051
8%~$149,066

Assumptions

  • No further contributions are made after today.
  • Returns compound annually at a constant rate; real markets fluctuate.
  • No inflation adjustment, taxes or fees are included in the base number.
  • Reaching a Coast number is encouraging, not a guarantee of retirement readiness.
  • Results are hypothetical and for education only — not financial advice.

View the formula →

Educational purposes only. Not financial advice. See the full methodology and disclaimer.

Worked examples

See how much you need invested today to "coast" to your retirement goal. Coast FIRE means your existing investments grow to your target without further contributions.

Example 1: Coast FIRE at 30 with a $1.5M goal

Current age: 30 · Target retirement age: 60 · Target nest egg: $1,500,000 · Expected return: 7%

Coast FIRE number
$197,051
Years to grow
30 years
Growth factor
7.6×

If you're 30 and want $1.5M by age 60, the model requires $197,051 invested today at a constant 7% annual return. Under that assumption, no further retirement contributions are needed for the balance to reach $1.5M by age 60. Real returns will not arrive in a straight line, so treat this as a threshold to stress-test, not a promise. Reaching it may give you more flexibility over future retirement contributions while you continue covering current living expenses.

Example 2: The cost of waiting — age matters

Same $1.5M goal, age 60 retirement, 7% return · different current ages

Age 25
$140,494
35 years to grow
Age 30
$197,051
30 years to grow
Age 35
$276,374
25 years to grow
Age 40
$387,629
20 years to grow

Every 5 years you wait to reach Coast FIRE costs you dearly. At age 25, you need $140,494. At 30, $197,051 — $56,557 more. At 35, $276,374 — $135,880 more than at 25. At 40, $387,629 — nearly triple what you'd need at 25. This is because compounding needs time: 35 years turns $140k into $1.5M (10.7× growth), but 20 years only turns $388k into $1.5M (3.9× growth). The lesson: the best time to start investing was 10 years ago. The second best time is now. Even small amounts invested early matter enormously because of the time they have to compound.

Example 3: Different goals, different Coast FIRE numbers

Age 30, retiring at 60, 7% return · different target nest eggs

Lean FIRE ($1M goal)
$131,367
$40k/year at 4%
Comfortable ($1.5M)
$197,051
$60k/year at 4%
Fat FIRE ($2M)
$262,734
$80k/year at 4%

Your Coast FIRE number scales linearly with your goal. Want to retire on $40,000/year (Lean FIRE, possible in low-cost areas or with paid-off housing)? You need $1M at retirement, which means $131,367 invested today at age 30. Want $60,000/year (comfortable in most U.S. cities)? $1.5M goal → $197,051 now. Want $80,000/year (Fat FIRE, including travel and hobbies)? $2M goal → $262,734 now. The beauty of Coast FIRE is that it gives you a concrete, achievable number to work toward — and once you hit it, you've won the game. You can choose to keep working and investing (growing beyond your goal), or coast and enjoy more freedom. Try our FIRE calculator to see when you could reach full FIRE.

All examples assume a constant 7% annual return and no additional contributions after reaching the Coast FIRE number. Actual returns will vary, and you should consider inflation, taxes, and fees when planning. See full disclaimer.

Coast FIRE, explained

What is Coast FIRE?
Coast FIRE is the stage where your current savings, compounding at a long-term average return, will reach your retirement target without any further contributions. Reaching the modeled Coast number can reduce the amount you need to keep contributing for retirement, but you still need income or other resources for current living expenses.
How is the Coast FIRE number calculated?
Divide your target retirement portfolio by (1 + assumed annual return) raised to the number of years until retirement. Example: $1,500,000 ÷ (1.07)^35 ≈ $140,494.
How is Coast FIRE different from regular FIRE?
Regular FIRE requires your whole portfolio to support spending at retirement. Coast FIRE only requires enough today to grow to that portfolio — contributions after "coast" are optional extras.
What return should I use?
There's no single right answer. Long-run U.S. equity averages are commonly cited around 6–10% nominal (historical ranges vary by source and period). Using a conservative range (5–7%) and testing sensitivity is the standard, honest approach.
Does this include inflation?
No. The base number uses a nominal return and a nominal target. Inflation erodes purchasing power over decades, so treat the result as a nominal planning figure — consider a 3% inflation assumption for a purchasing-power view.
What happens if the market crashes after I reach Coast FIRE?
This is the biggest risk of Coast FIRE. If you stop contributing right before a major market crash (like 2008 or 2020), your portfolio could drop 30–50%, and without new contributions, it might take years to recover. The 2008 crash: a $200k portfolio dropped to ~$120k and took until 2012 to recover. If you were counting on that $200k to grow to $1.5M by 60, a 4-year delay could mean falling short. Strategies to mitigate: (1) don't stop contributing entirely — even small contributions help, (2) keep a 1–2 year cash buffer so you don't have to sell depressed assets, (3) use a more conservative return assumption (5–6% instead of 7%), (4) consider a "Coast FIRE + part-time work" hybrid where you earn enough to cover living expenses but don't need to save more. Coast FIRE gives you flexibility, not a guarantee.
Can I use Coast FIRE to switch careers or take a sabbatical?
Absolutely — this is one of the most powerful applications of Coast FIRE. Once your investments are on track to reach your retirement goal without further contributions, you have the freedom to: (1) Switch to a lower-paying, more meaningful career — you don't need the high salary anymore because your retirement is already funded. (2) Take a sabbatical — travel, learn, or care for family for 6–18 months without derailing your retirement. (3) Work part-time — earn enough to cover living expenses while your retirement portfolio grows untouched. (4) Start a business — pursue entrepreneurship without the pressure of needing it to fund retirement. The key insight: Coast FIRE buys you optionality. You're not financially independent (you still need income for living expenses), but you're no longer trapped by the need to maximize salary. This is why many people in the FIRE community consider Coast FIRE the most practical and achievable form of financial freedom.

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Related reading

📖 FIRE Movement Guide
How Coast FIRE fits into the broader path to financial independence.→ What Is Coast FIRE?
The middle path that lets you stop saving for retirement early.→ FIRE, the 4% Rule, and Your FIRE Number
Understand the numbers behind financial independence.→ How Much Do You Need to Retire?
A framework for your full retirement target.→

Last reviewed: September 2026.

Continue your plan

Use these related resources to put this result in context: what Coast FIRE means · retirement calculator · FIRE calculator.

The 4% rule is a historical withdrawal framework, commonly studied over 30-year periods. It does not guarantee success or preservation of principal: principal can decline or be depleted. Results depend on allocation, fees, taxes, inflation, retirement length and the sequence of returns.