Notes on FI/RE math and how to think about your own numbers.
The 4% rule turns a year of spending into a retirement number. Here is where it comes from, why retiring early breaks it, and a calculator that applies the adjusted version.
September 7, 2026 · 4 min read
Barista FIRE means leaving full-time work years before your portfolio can support you, and letting a part-time income cover the gap. Here is how the math works and a calculator for your own numbers.
September 7, 2026 · 4 min read
Lean FIRE retires on less than you spend today, fat FIRE on more. The difference in the target is bigger than it looks, and the difference in the date is bigger still. A side-by-side calculator.
September 7, 2026 · 3 min read
Moving somewhere cheaper lowers what you need to retire and raises what you can save, at the same time. Here is why it is the strongest single lever most people have, and a calculator for the move.
September 7, 2026 · 3 min read
What "coast FI" actually means, how to tell if you've hit it, and why the number that matters isn't your net worth.
August 23, 2026 · Updated September 7, 2026 · 3 min read