Coast FIRE Calculator
This Coast FIRE calculator estimates whether your current portfolio is large enough to grow to a retirement target without needing additional contributions.
Calculator
Adjust the inputs to explore different scenarios instantly.
Coast FIRE target today
$276,374
How it works
Enter your current age, retirement age, current investments, annual spending goal, and expected annual return. The calculator estimates a retirement target using a safe withdrawal rate, then discounts that target back to today using the expected return assumption.
Example calculation
Someone with $220,000 invested at age 35 may be closer to Coast FIRE than expected if retirement is still decades away and spending needs are moderate, because time does much of the heavy lifting.
Why this matters
Coast FIRE gives users a milestone between full financial independence and traditional retirement planning. It can help clarify whether saving goals are still aggressive or already ahead of schedule.
Coast FIRE is a compounding checkpoint
Coast FIRE asks a specific question: if you stopped adding new retirement contributions, could your current investments grow enough to reach your retirement target by the time you need them?
That makes it different from a standard retirement calculator. The focus is not only the final nest egg, but whether your current balance is already large enough for time and compounding to do much of the remaining work.
What the Coast FIRE estimate checks
- Estimates a retirement portfolio target from spending and withdrawal-rate assumptions.
- Discounts that target back to today using your time horizon and expected return.
- Compares the Coast FIRE number with your current invested balance.
- Helps show whether you may be ahead, behind, or close to a compounding milestone.
When to test Coast FIRE
- When deciding whether retirement contributions can slow down temporarily.
- When evaluating career flexibility, lower-stress work, or reduced hours.
- When comparing current savings progress with a long-term retirement target.
- When you want a milestone between normal retirement saving and full financial independence.
Example: time can carry more of the load
A 35-year-old with decades before retirement may need far less invested today than the final retirement target because compounding has time to work.
The same balance at age 55 would be much less likely to coast because there are fewer years left for growth.
- Current age and retirement age entered by the user
- Annual spending target converted into a portfolio target
- Expected return used as a long-term assumption
- No future contributions included in the Coast FIRE test
Coast FIRE is most useful as a progress checkpoint, not a reason to ignore uncertainty or stop planning.
How the Coast number is estimated
The calculator estimates a retirement portfolio target by dividing expected annual retirement spending by the withdrawal-rate assumption.
It then discounts that future target back to today using the expected annual return and years until retirement. The result is the approximate balance needed now to coast without additional contributions.
How to read the Coast result
If your current balance is above the Coast FIRE estimate, the projection suggests you may be on track under the assumptions. It does not guarantee success because returns, inflation, taxes, spending, and life events can change.
If your balance is below the estimate, the gap shows how much more current savings, future contributions, lower spending, later retirement, or higher returns would need to help.
Coast FIRE mistakes
- Treating Coast FIRE as permission to stop saving permanently.
- Using an aggressive return assumption without testing lower returns.
- Ignoring inflation, taxes, fees, healthcare, and changing spending needs.
- Confusing Coast FIRE with full financial independence today.
- Leaving out accounts that are not truly invested for retirement.
Ways to stress-test the result
- Run lower-return scenarios before making life changes.
- Compare the result with a standard retirement savings projection.
- Revisit the estimate after major market moves or spending changes.
- Keep emergency savings separate from retirement investments.
Frequently asked questions
What is Coast FIRE?
Coast FIRE means having enough invested now that compounding alone could potentially grow it to your retirement target by retirement age.
Does this assume I stop contributing entirely?
Yes. The calculation asks whether your current invested balance could grow enough on its own without future contributions.
Why does the withdrawal rate matter?
The withdrawal rate determines the retirement portfolio target. A lower withdrawal rate requires a larger final nest egg.
Is the return assumption guaranteed?
No. It is only a planning assumption, so real-world results may differ significantly.