🧮 Calculator ✓ Free ⚡ Instant 🔒 Private

Coast FIRE Calculator

Calculate your Coast FIRE number.

🧮

Coast FIRE Calculator

Your Results

Enter your details to see results.

How This is Calculated

Formula:

Coast FIRE target = FIRE Number / (1 + r)^Years

Calculates target nest egg today that will grow to your retirement number by retirement age without additional saving. r is interest rate.

Sources & Assumptions: FIRE budgeting compound interest formulas based on the Trinity Study.

What Is Coast FIRE?

Coast FIRE is a variant of the Financial Independence, Retire Early (FIRE) movement. The core idea: if you save and invest aggressively early in your career, you reach a portfolio value at which compound interest alone — without any additional contributions — will grow your nest egg to your full retirement target by your intended retirement age. Once you hit your Coast FIRE number, you can “coast” — stop making retirement contributions — and simply let compound growth do the work. This frees you to switch careers, reduce hours, pursue passion projects, or take lower-stress jobs without sacrificing your retirement security. The mathematical concept is essentially working backwards from your full FIRE number using a reverse compound interest discount.

Formula Used

Formula:

Coast FIRE Number = Full FIRE Target ÷ (1 + Annual Growth Rate)^Years Until Retirement
Sources & Assumptions: Calculated using discounted present value compound interest methodology. Full FIRE Number assumes 4% safe withdrawal rate per the Trinity Study.

ⓘ Disclaimer: Results are estimates for educational purposes only and do not constitute financial, tax, or investment advice. Always consult a qualified financial professional before making significant financial decisions.

Results are for informational purposes only and do not constitute financial advice. Always consult a qualified financial professional.