FIRE / Retirement Number Calculator

About this calculator

This calculator applies the 4% safe withdrawal rate (also called the 25x rule) from the Trinity Study to estimate the investment portfolio needed to retire and live off withdrawals indefinitely: it multiplies annual spending by 25, the inverse of 4%. A lower withdrawal rate, like 3.5%, produces a larger and more conservative target for anyone worried about market downturns early in retirement.

It's the core calculation behind the FIRE (Financial Independence, Retire Early) movement, used by people planning to leave traditional work in their 30s or 40s as well as conventional retirees checking whether their 401(k) or pension savings can support their lifestyle. Entering current savings and a monthly contribution also shows roughly how many years remain until the target is reached.