FIRE Planning Guide (2026): Assumptions, Math, and Withdrawal

The FIRE-planning content here is organized so a planner can move from how much do I needhow do I withdraw itwhat breaks the plan in a single sitting.

The connecting thread is sequence risk: getting hit by a bear market in your first five years of retirement is the single biggest threat, and most retirement calculators ignore it. Every spoke here ties back to that constraint.

26 articles · last reviewed 2026-05-17 · part of the QuantCalc research library

How much you need

FIRE variants (Coast, Barista, Lean, Fat)

Withdrawal rules

Sequence-of-returns risk

Tax/Bracket interactions

Social Security timing