Coast FIRE Calculator
Find out how much you need invested today to coast to financial independence by your target retirement age — without adding another dollar.
How Coast FIRE works
Coast FIRE is the moment your existing investments are big enough to grow into your full retirement number on their own. Once you hit it, you can stop saving for retirement and only need to earn enough to cover today's expenses — your future is already funded by compounding.
The math behind the number
This calculator first computes your FIRE number (annual retirement spending divided by your safe withdrawal rate). It then discounts that target back to today using your expected real return and the years until retirement, giving the Coast FIRE number — the amount you'd need invested right now to coast.
A planning estimate, not a guarantee
Returns vary, inflation moves, and life changes. Use conservative assumptions and revisit the number as your situation evolves. The most useful habit is tracking your actual invested net worth over time and comparing it against your coast target.
Coast FIRE — FAQ
What is Coast FIRE?
Coast FIRE is the point where your invested assets are large enough that, without adding another dollar, they'll grow to your full financial-independence number by your target retirement age. After reaching it you only need to cover current expenses — your retirement is already 'coasting'.
How is the Coast FIRE number calculated?
First find your FIRE number: annual retirement spending divided by your safe withdrawal rate (e.g. 4% → spending × 25). Then discount it back to today using your expected real return over the years until retirement: Coast number = FIRE number ÷ (1 + return)^years.
What return and withdrawal rate should I use?
Many people model a 5–7% real (after-inflation) return and a 4% safe withdrawal rate, but these are assumptions, not guarantees. Use conservative figures and treat the result as a planning estimate, not a promise.
Is Coast FIRE the same as being able to retire?
No. Coast FIRE means you can stop investing for retirement, not stop working entirely — you still need income to cover today's living costs until you actually retire and begin drawing down.