How to count outs in Poker

Count outs in three steps

An out is an unseen card that helps your hand. Start by counting cards that complete a particular draw, then check whether those cards are likely to win against your opponent.

1. Identify what you need: a card of one suit, a missing rank, or a card that pairs your hand.
2. Remove visible cards and count each remaining card only once, even if it completes more than one draw.
3. Check the opponent's possible hands. Improving your hand is not the same as taking the lead or keeping it until showdown.

Worked example: nine cards to complete a flush

Your hand

Board

You can see four of the 13 hearts: two in your hand and two on the flop. The other nine hearts complete your flush. With only your hand and the flop known, 47 cards are unseen.

Outs reference chart

Test yourself: avoid counting an out twice

Your hand

Board

How many different cards complete a straight or a flush on the turn?

Dirty outs: when your card also helps your opponent

Your hand

Board

Suppose your opponent holds Qc Qd. The 2h completes your flush, but also gives the opponent a full house. Counting every heart as a winning out would be wrong. Even when you take the lead on the turn, the river can change the result.

From outs to probability: one card or two?

For nine hearts from the flop, the next-card probability is 9 / 47, about 19.1%. Completing the flush by the river is about 35.0%: 1 - (38 / 47) × (37 / 46). These calculations assume only your two cards and the flop are known.

Multiply outs by 2 for a rough one-card estimate, or by 4 for two cards from flop to river. The two-card estimate does not mean a flop call buys both cards: another bet may follow on the turn.

These are probabilities of completing the draw, not exact equity against an opponent. With many outs, the rule of 4 becomes less accurate.