Short, honest explainers for the ideas behind the calculator. No jargon, no hype, and no financial advice. Just how the numbers actually work, written by the person who built the tool.

• How Coast FIRE is calculated (with a worked example)

  What Coast FIRE really means, the exact method, and one full example start to finish. Plus how it differs from regular FIRE.

• A FIRE calculator that includes taxes and debt

  Most free calculators run one formula and ignore taxes, debt, and inflation. Here is why that misleads you, and what changes when you model them month by month.

• FIRE, Coast FIRE, Lean FIRE, and Barista FIRE

  The four milestones explained simply: what each one means, who it suits, and the usual order you reach them.