Pot Odds and Outs
Last reviewed · CardLore editorial
There is one calculation in poker that pays for itself immediately, and it is arithmetic rather than mathematics. Count the cards that would complete your hand, work out how often one of them arrives, and compare that to the price you are being asked to pay. If the price is better than the chance, the call is worth making.
Nothing here predicts the next card. It tells you whether a decision is worth repeating, which is the only kind of edge a card game offers.
Counting your outs
An out is any card still in the deck that would give you the best hand. Counting them accurately is the whole skill; the rest is a short multiplication.
Common draws and their outs
| Draw | Outs | Why |
|---|---|---|
| Flush draw | 9 | Thirteen of a suit, four already seen |
| Open-ended straight draw | 8 | Four cards at each end |
| Inside straight draw | 4 | One rank fills the gap |
| Two overcards | 6 | Three of each rank remain |
| Pair to three of a kind | 2 | Two matching cards left |
| Flush draw with an open-ended straight | 15 | Nine plus eight, minus the two counted twice |
The rule of two and four
With your outs counted, this converts them into a percentage accurately enough for a decision at the table.
- One card to come: multiply your outs by two.
- Two cards to come: multiply your outs by four.
A flush draw with nine outs is therefore roughly 18 per cent to complete on the next card, and roughly 36 per cent across both the turn and the river. The true figures are 19.1 and 35.0, which is close enough.
Outs converted to chances
| Outs | Next card | Both cards |
|---|---|---|
| 2 | 4% | 8% |
| 4 | 9% | 17% |
| 6 | 13% | 24% |
| 8 | 17% | 32% |
| 9 | 19% | 35% |
| 12 | 26% | 45% |
| 15 | 33% | 54% |
Use the four-times figure only when you expect to see both cards without paying again — typically when you or your opponent is already all-in. If another bet is coming on the turn, the two-times figure is the honest one.
Turning the pot into a price
Pot odds are the ratio between what you can win and what you must pay. The pot contains $80, an opponent bets $20, so you are paying $20 to win $100. That is five to one, or in percentage terms you need to win about 17 per cent of the time to break even.
- Add up the pot after the betEverything in the middle plus the bet you are facing. In the example, $80 plus $20 is $100.
- Divide your call by that total$20 into $120 — the pot, the bet and your call — gives roughly 17 per cent. That is the share of the time you need to win.
- Compare it to your chance of hittingA nine-out flush draw is 19 per cent on the next card. 19 is more than 17, so the call is worth making.
- Check what the hand costs after this streetIf a large bet is certain on the next card, the real price is higher than this one bet, and a marginal call becomes a fold.
Implied odds and reverse implied odds
Pot odds measure the money already on the table. Implied odds take account of the money you expect to win later if your draw comes in.
A call that is marginally wrong on pot odds can be right if your opponent will pay you a large bet when you hit. That is most plausible when your draw is hidden — a straight that completes on a rainbow board — and least plausible when it is obvious, such as a third heart arriving on the river.
The reverse also exists. Reverse implied odds describe the money you will lose when you complete your hand and it is still second best: the lower end of a straight, or a flush that is not the nut flush. Chasing a non-nut flush in Omaha is the textbook example and it is expensive.
What this does not do
- It does not predict the next card. A correct call loses more often than it wins whenever the draw is under 50 per cent.
- It does not make a losing game profitable. Pot odds are one input among several, and the others are reading the table and choosing the hands you enter.
- It does not apply to games without betting. Hearts and Spades have odds worth counting, but no pot to price them against.
- It does not change the house edge in blackjack, where you are not competing for a pot.
The right expectation is modest: the calculation stops you making the calls that lose money fastest. Over a long run that is the difference between a losing player and a break-even one.
Common questions
What is an out?
A card still unseen that would give you the best hand. Nine hearts remain for a flush draw when you can see four, so a flush draw has nine outs.
Does the rule of four always work?
Only when both remaining cards will be seen without further betting. If a bet is coming on the next street, use the rule of two for the next card alone.
Should I count outs that pair my hand?
Only if that pair would win. Against an opponent representing a strong hand, pairing a low card is usually not an out at all.
Do pot odds apply before the flop?
Yes, but the calculation is vaguer because so many cards are still to come. Before the flop most decisions are better made on position and hand strength; see Table Position.