What counts as a clean out?
An out should improve you to a hand that is likely to win. If completing your draw can also make an opponent a stronger hand, some or all of those cards may be “dirty” and should not be counted at full value.
Exact simple assumptions
For one card from the flop, this tool uses outs ÷ 47. For two cards from flop to river, it uses the probability of missing on both remaining cards and subtracts that from 100%. This does not model opponent ranges, redraws or card removal beyond your entered outs.
Useful shortcut: the familiar rule of 2 and 4 is a mental approximation. This tool shows the exact simple probability for comparison.