What is Coast FIRE and how is it different from full FIRE?

Coast FIRE means you've already invested enough that, without adding another dollar, compound growth alone will reach your full retirement number by your target age. You still work — but only to cover current living expenses, not to keep saving for retirement. For example, if you need $1.5 million at 65 and you're 35 with about $400,000 invested, growth at roughly 5% real over 30 years gets you there on its own. Reaching Coast FIRE buys flexibility: you can take a lower-stress job, switch careers, go part-time, or stop contributing to retirement accounts without derailing the plan. It's different from full FIRE, where your portfolio covers all your spending and work becomes optional. Coast is usually the first major milestone people hit. Estimate your Coast number at wealthserene.com/tools/fire-calculator.