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Guides
Plain-English walkthroughs of exactly how the FIRE Age and FIRE Number calculators work — the formulas, the ordering rules, and the logic behind every number.
How the FIRE Number Calculator works
A walkthrough of the exact logic behind the FIRE Number Calculator — the quick target formula, the debt projection, and the real, simulation-backed verdict underneath it.
How the FIRE Age Calculator works
A walkthrough of the exact logic behind the FIRE Age Calculator — nominal-vs-real handling, the decumulation order, pension locking, and how the FIRE age itself gets found.