In-depth guides and resources to help you make the most of the FIRE Calculator and master the underlying financial concepts.
Open FIRE CalculatorFinancial Independence, Retire Early (FIRE) is built on a single mathematical identity: when your invested assets equal 25× your annual expenses, a 4% annual withdrawal should sustain your portfolio indefinitely based on historical U.S. market returns. These guides explore the full FIRE spectrum — from traditional FIRE (strict 4% rule) to Lean FIRE (sub-$40k expenses), Fat FIRE (luxury spending), and Coast FIRE (stop contributing and let the portfolio grow) — with the data behind each approach and its real-world viability.
The guides tackle the hard questions: how to handle the ACA subsidy cliff when your income drops in early retirement, how to bridge the gap between retiring early and Medicare eligibility at 65, and how to structure Roth conversion ladders to access tax-advantaged funds before 59½ without penalty. All projections use 2026 IRS contribution limits (IRS Notice 2025-67), 2026 ACA benchmark premium data, and Monte Carlo simulation concepts to stress-test your FIRE number against sequence-of-returns risk.
Everything you need to know about Financial Independence, Retire Early. Calculate your FIRE number, explore Lean FIRE and Coast FIRE, and build your action plan.
Understand the three main types of FIRE (Financial Independence, Retire Early) and calculate which one matches your lifestyle and goals with real numbers and examples.