How this calculator works
Coast FIRE starts with a retirement spending target and withdrawal rate, then discounts that future target back to today's age using an assumed real return. It asks how much would need to be invested now if no new retirement contributions were made.
What Coast FIRE means
Reaching the threshold means the modeled portfolio could grow toward the retirement target without additional contributions. It does not mean work can stop today: current living costs still need another source of income.
Real-world example
A 30-year-old has 35 years for compounding before age 65. That long runway can make the required balance today much smaller than the final retirement target. Waiting even five years can materially raise the Coast number.
Common mistakes
- Confusing Coast FIRE with full financial independence.
- Assuming a constant return will occur smoothly.
- Omitting taxes, fees, or major future spending changes.
- Stopping retirement saving without a margin of safety.
When to use this calculator
Use it to explore career flexibility, contribution changes, and the value of starting early. Revisit the estimate as spending goals, age, or portfolio assumptions change.
FAQ
Does Coast FIRE mean I can retire now?
No. It means the modeled retirement portfolio may grow to its target without new contributions; current expenses still need funding.
Should I stop contributing after reaching Coast FIRE?
That is a personal risk decision. Continued contributions can provide margin for lower returns, higher spending, or earlier retirement.
Why is real return used?
It keeps both future spending and the discounted target in today's purchasing power.