Coast FIRE Calculator
Find your Coast FIRE number: the amount you need invested today so that, with no further contributions, compound growth alone carries you to financial independence by your target retirement age. Enter your details to see whether you are already coasting and the age your investments reach your FI number on their own.
A 30 year old who wants to retire at 65 and spend $40,000 a year needs a $1,000,000 FI number (25x expenses). At 7% real returns, that target discounts to a Coast FIRE Number of about $93,700 today. So with $100,000 already invested, this person is already coasting and can stop contributing now, while compounding alone carries them to financial independence by age 65.
Enter Your Parameters
See if compounding alone can carry you to FIResults
Your Coast FIRE number and coasting statusEnter your details and click calculate to see your Coast FIRE number and whether you can stop contributing.
Frequently Asked Questions
Understanding the Coast FIRE milestone
What is Coast FIRE?
Coast FIRE is the point where your existing investments, left completely untouched, will grow to your full financial independence number by your target retirement age. Once you reach your Coast FIRE Number you no longer need to save for retirement at all; you only need to earn enough to cover your current living expenses, and compounding does the rest of the work.
It is the most popular early milestone in the FIRE movement because it arrives long before full FIRE. Many people hit Coast FIRE in their thirties, which frees them to switch to a lower stress job, work part time, or take a career break without derailing their retirement.
How is the Coast FIRE Number calculated?
It takes two steps. First, your FI number is your expected annual retirement spending divided by your safe withdrawal rate. At a 4% rate that is the familiar 25x rule, so $40,000 of spending implies a $1,000,000 FI number.
Second, that future target is discounted back to today using your expected real return and the number of years until retirement. The formula is your FI number divided by (1 plus your real return) raised to the power of the years to retirement. The longer your runway and the higher your return, the smaller the amount you need invested today.
Your Privacy is Protected
All calculations run entirely in your browser. We never collect, store, or transmit any data you enter into this calculator. There are no APIs, no server requests, and no logs - your financial information stays on your device and disappears when you close the page.
For informational and educational purposes only — not investment advice.