4% rule
A retirement rule of thumb: withdraw 4% of your savings in the first year, then raise that dollar amount for inflation each year after.
It comes from research on past US stock and bond returns over 30-year retirements. It is a planning guide, not a promise. Returns vary and can be negative.
Turned around, it gives a savings target: multiply the yearly amount you need from savings by 25.
Example
On $650,000, the first-year withdrawal is $650,000 × 4% = $26,000. With 3% inflation, year two is $26,000 × 1.03 = $26,780.