Calculations • • By Sarah Jenkins
How to Calculate Your Coast FIRE Number Step-by-Step
A detailed breakdown of the mathematical formula behind your Coast FIRE milestone.
How to Calculate Your Coast FIRE Number Step-by-Step
Calculating your Coast FIRE number requires four essential inputs:
- Your desired retirement spending
- Your Safe Withdrawal Rate (SWR)
- Your expected annual real rate of return
- The number of years until you reach retirement
The Formula
To find out how much you need today:
- Calculate your target retirement nest egg: Spending / SWR.
- Discount that target by your real annual return over the remaining years.
Using our interactive calculator on the home page makes this calculation instant and visually clear!