This Coast FIRE calculator shows how much you need invested today so that your savings can grow to your retirement number without adding another dollar. If you have already reached it, you only need to earn enough to cover your current living costs.
What is Coast FIRE?
Coast FIRE is the point where your existing investments, left alone to compound, are expected to reach your full FIRE number by your chosen retirement age. You still work, but you no longer need to save for retirement, which gives you freedom to take a lower-paid job, work part time or take a career break.
Coast FIRE formula
FIRE number = yearly spending ÷ withdrawal rate
Coast FIRE number = FIRE number ÷ (1 + return)years until retirement
The return is after inflation, so all results are in today’s money.
Worked example
You are 30 and plan to retire at 65, which is 35 years away. You expect to spend $40,000 a year and use a 4% withdrawal rate, so your FIRE number is $1,000,000. With a 5% return after inflation, your Coast FIRE number today is about $181,290. If you have $60,000 invested, you still need about $121,290 more. Left alone, that $60,000 would reach $1,000,000 at about age 88.
Frequently asked questions
Is Coast FIRE the same as retiring early?
No. With Coast FIRE you keep working to pay your current bills, but you stop saving for retirement. Full FIRE means you can stop working altogether.
What happens if returns are lower than expected?
Your savings would fall short of your FIRE number. Many people keep investing a little after reaching Coast FIRE, or test a lower return in the calculator, to leave a margin of safety.
How is this different from the regular FIRE calculator?
The FIRE calculator includes ongoing contributions and tells you when you can stop working. This calculator assumes no new contributions and tells you whether you can stop saving.
For education only, not financial advice.