๐ Timeline to FIRE
What Is a FIRE Number and How Do You Calculate It?
Your FIRE number is the total investment portfolio value you need to sustain your lifestyle indefinitely without earning income. The concept underpins the Financial Independence, Retire Early (FIRE) movement and is rooted in the 1998 Trinity Study, which found that a 4% annual withdrawal rate from a stock/bond portfolio has historically sustained withdrawals for 30+ years with a high probability of success.
The math is simple: FIRE Number = Annual Expenses รท Safe Withdrawal Rate. At 4% SWR with $60,000 in annual expenses, your FIRE number is $1,500,000 ($60,000 รท 0.04). Every dollar you reduce from your annual spending reduces your FIRE number by $25. Every extra dollar you save and invest brings you closer while simultaneously reducing the lifestyle overhead you need to sustain.
The time to reach your FIRE number depends on your savings rate. The FIRE community's most important insight is that your savings rate โ not your income โ determines when you can retire. A person earning $50,000 and saving 50% ($25,000/year) will typically reach FIRE faster than someone earning $200,000 and saving 10% ($20,000/year).
The Four FIRE Variants Explained
- Regular FIRE โ Targets full financial independence at a moderate lifestyle. Typically requires $1M-$2.5M for most US households with annual expenses of $40,000-$100,000.
- Lean FIRE โ Aggressively frugal lifestyle, usually targeting under $40,000/year in expenses. Lower FIRE number means reaching it faster, but leaves less margin for emergencies or lifestyle upgrades.
- Fat FIRE โ High-spending financial independence, usually $100,000+ in annual expenses. Requires larger portfolios ($2.5M+) but provides maximum lifestyle flexibility. Often pursued by high-income professionals.
- Barista FIRE โ A hybrid approach where you partially retire, earning enough from part-time work to cover basic expenses (like health insurance), while your investments cover the rest. Lower portfolio required; popular with those who enjoy working but want flexibility.