The Coast FIRE Compound Simulator
Enter your numbers below and discover your Coast FIRE age — the magical moment your money works harder than you ever did.
Enter your details and hit calculate to discover your Coast FIRE status.
Your compound growth curve will appear here after calculation.
Coast FIRE is the point where your invested portfolio is large enough that — even if you never invest another dollar — compound interest alone will grow it to your retirement target by your desired retirement age. You've "coasted" to financial independence.
We use the compound interest formula: A = P(1 + r/n)nt, where P is your current portfolio, r is the annual return rate, n is compounding frequency (annually), and t is time in years. We solve backwards to find the minimum P needed today.
Your "Coast Number" is the minimum portfolio value you need right now so that compound growth alone reaches your target. If your current portfolio exceeds this number, congratulations — you've already hit Coast FIRE!
This calculator assumes a constant annual return and does not account for inflation, taxes, fees, or market volatility. Real-world returns will vary. Use this as directional guidance, not a precise financial plan. Consult a financial advisor for personalized advice.