Backdoor draw
A draw that needs both the turn and the river to complete — for example three cards to a flush on the flop. Backdoor draws add a few percentage points of equity and make hands worth continuing with.
Frequently asked questions
What is a backdoor draw in poker?
A draw that is two cards away — three to a flush or three to a straight, needing both the turn and the river to cooperate. Also called a runner-runner draw when it actually gets there.
What are the odds of hitting a backdoor flush?
About 4% from the flop — roughly one time in twenty-four. On its own that is nothing to build a hand around.
So why does it matter?
Because 4% of extra equity is often what makes a marginal call correct rather than incorrect, and because the backdoor card gives you a credible hand to bet on a later street. Solvers continue with backdoor-equity hands and fold their equity-free equivalents for exactly this reason.