Coast FIRE
How to Use This Coast FIRE Calculator
This calculator determines whether your current retirement savings, left untouched, will grow to your full retirement number by traditional retirement age — meaning you no longer need to save more, only cover current expenses.
How It’s Calculated
Coast FIRE Number = Target Retirement Number / (1 + r)^years remaining
If your current savings exceed this number, you’ve “coasted” and future contributions become optional.
Example
Targeting a $1.5M retirement number at 65, with 25 years to go and a 7% return, requires a current balance of only about $276,000 to coast — anything above that means new contributions are purely optional upside.
Frequently Asked Questions
What’s the difference between Coast FIRE and regular FIRE?
Regular FIRE requires fully funding your retirement number before stopping work. Coast FIRE only requires your current savings to be enough to grow into that number on its own by retirement age, letting you work purely to cover living costs in the meantime.
Does Coast FIRE mean I can stop working entirely?
No — you’d still need income to cover current expenses. Only the retirement-saving obligation is coasted, not your day-to-day costs.
What return rate should I use to calculate my Coast FIRE number?
A conservative long-run average of a 6% to 7% real return is standard, since this projection runs over one or more decades and short-term volatility mostly averages out.