Coast FIRE Calculator

Traditional FIRE means you have enough money to retire immediately and live off your investments indefinitely. Coast FIRE means you have enough invested that it will grow to your FIRE number by your target retirement age without additional contributions. Coast FIRE is reached earlier and requires less initial savings, but you still work until your planned retirement age (though you don't need to save for retirement anymore).

The amount needed for Coast FIRE depends on several factors: your current age, planned retirement age, desired retirement expenses, expected investment returns, and inflation rate. Generally, Coast FIRE requires significantly less than traditional FIRE—often 30-50% less depending on how many years until retirement. Use our calculator above to get your personalized Coast FIRE number.

The 4% rule states that you can safely withdraw 4% of your portfolio each year in retirement without running out of money (historically based on a 30-year retirement period). To calculate your FIRE number, multiply your annual expenses by 25 (which is 1/0.04). For Coast FIRE, you calculate what your portfolio needs to be today to grow to that FIRE number by your retirement age, accounting for compound growth.

Absolutely! Reaching Coast FIRE means you don't have to contribute anymore, but you certainly can if you want to. Additional contributions will allow you to retire even earlier, have a larger retirement fund, increase your retirement spending, or provide extra security against market downturns. Many people continue contributing but at a much lower rate, giving them more flexibility in their current lifestyle.

Conservative estimates use 5-7% annual returns (after inflation), which aligns with historical stock market performance. More aggressive investors might use 8-10%, while more conservative ones might use 4-5%. It's wise to calculate multiple scenarios. Remember to account for inflation separately—if you expect 7% nominal returns and 3% inflation, your real return is approximately 4%. Our calculator allows you to adjust these assumptions to match your risk tolerance.

Coast FIRE is more achievable than traditional FIRE for most people because it requires less savings and gives more time for compound growth. However, it still requires disciplined saving in your 20s, 30s, or 40s, and the ability to earn enough to cover living expenses (without saving) after reaching Coast FIRE. It's most realistic for people who start saving early, have moderate income, and are comfortable working until traditional retirement age rather than retiring extremely early.

Market volatility is a valid concern with Coast FIRE. If you stop contributing and a major downturn occurs, you may fall below your Coast FIRE number. Strategies to mitigate this include: building a buffer above your Coast FIRE number before stopping contributions (e.g., 10-20% extra), maintaining flexibility to resume contributions if needed, using conservative return assumptions in calculations, and diversifying investments properly. Many Coast FIRE adherents continue making small contributions or adjust their retirement age if needed.

Coast FIRE provides tremendous career flexibility. Once you reach your Coast FIRE number, you only need to earn enough to cover current living expenses—you don't need to save for retirement anymore. This allows you to: take a lower-paying but more fulfilling job, work part-time, start a business with lower risk, take career breaks for travel or family, pursue creative endeavors, or negotiate better work-life balance. Many people use Coast FIRE as a stepping stone to full FIRE or as a permanent lifestyle choice.

This depends on your age and risk tolerance. Younger people (under 40) might want to exclude Social Security for conservative planning, as the program may change by retirement. Older individuals closer to retirement can more confidently include projected benefits. A balanced approach is to calculate Coast FIRE without Social Security as your baseline, then view any social security benefits as a bonus that allows for higher spending or additional security. You can also calculate multiple scenarios with different social security assumptions.

Review your Coast FIRE calculations annually or when major life changes occur (marriage, children, career change, home purchase, etc.). Market performance, changes in expenses, inflation rates, and time remaining until retirement all affect your Coast FIRE number. Regular check-ins ensure you stay on track and can adjust if needed. Many people track their progress quarterly but only make significant decisions after annual reviews. Use our calculator to run different scenarios and see how changes affect your timeline.