Work out poker hand odds instantly with clear inputs, formula shown and shareable results.
With two cards to come the exact chance is one minus the product of the two miss probabilities over 47 and 46 unseen cards; the rule of 4 and 2 multiplies outs by four or two as a mental shortcut. The shortcut overstates a nine-out flush draw by about a point and a half, which matters when a pot odds decision is close.
Two cards to come
P(hit) = 1 - (47 - outs)/47 x (46 - outs)/46
Rule of 4 and 2
approximate % = outs x 4 with two cards to come, outs x 2 with one
P(hit) = 1 - (47 - outs)/47 x (46 - outs)/46. With two cards to come the exact chance is one minus the product of the two miss probabilities over 47 and 46 unseen cards; the rule of 4 and 2 multiplies outs by four or two as a mental shortcut.
The shortcut overstates a nine-out flush draw by about a point and a half, which matters when a pot odds decision is close.
Enter number of outs, cards still to come. The defaults shown are a realistic worked example — swap in your own figures to get a result you can use.