There is no time at the table to work out exact probabilities, so players use shortcuts. The place this shortcut goes wrong most often is multiplying by 4 when the situation calls for 2 — which makes an unprofitable call look profitable.
This page lists the number of outs and the hit probability for the draws you will actually see, and explains when each rule applies. For how to compare that probability against the price you are being offered, see what pot odds are.
- ✓This call only buys the next card → use outs × 2.
- ✓This call buys both the turn and the river → only then use outs × 4.
- ✓Facing a bet on the flop is usually the first case, because you will normally have to pay again after the turn.
- ✓Above 8 outs, × 4 clearly overestimates and needs to be adjusted down.
- ✓Cards that complete your hand but still lose cannot be counted as full outs.
What separates the two rules
The difference comes down to one thing: how many cards does this payment buy you?
- One card → outs × 2
- Two cards → outs × 4
When you face a bet on the flop, your money only buys the turn. Once the turn lands, your opponent will often bet again, and you have to pay a second time to see the river. That is a × 2 spot.
Only when no further payment is coming — for example when your opponent is already all in — does a single payment buy you two cards, and only then does × 4 hold.
Outs for the common draws
| Draw | Outs | Why |
|---|---|---|
| Flush draw | 9 | 13 of that suit, minus the 4 you can already see |
| Open-ended straight draw | 8 | Four cards at each end |
| Gutshot straight draw | 4 | Only the one card in the middle |
| Two overcards | 6 | Three cards to pair each one |
| Pocket pair to a set | 2 | Two cards of that rank remain |
| Set to a full house or quads | 7 | Six to pair the board, plus one of your own rank |
| Flush draw plus open-ended straight | 15 | After removing the cards the two draws share |
| One pair to two pair or trips | 5 | Two to pair your kicker, three to trip up |
Hit probability
Seeing only the next card (× 2):
| Outs | Estimate | Actual |
|---|---|---|
| 4 | 8% | 8.7% |
| 6 | 12% | 13.0% |
| 8 | 16% | 17.4% |
| 9 | 18% | 19.6% |
| 15 | 30% | 32.6% |
Seeing both the turn and the river (× 4):
| Outs | Estimate | Actual |
|---|---|---|
| 2 | 8% | 8.4% |
| 4 | 16% | 16.5% |
| 6 | 24% | 24.1% |
| 8 | 32% | 31.5% |
| 9 | 36% | 35.0% |
| 15 | 60% | 54.1% |
The pattern is clear: the estimate is accurate with few outs and × 4 overestimates with many. At 15 outs the shortcut is almost 6 percentage points high, which is enough to change the answer when you are deciding whether to stack off.
The correction is simple: above 8 outs, take × 4 and subtract (outs − 8). Fifteen outs becomes 60 − 7 = 53%, almost exactly the true 54%.
Discount your outs first
The number you counted is a ceiling, not what you can actually use. Adjust down in these cases:
- The out pairs the board. The card that makes your flush can also give your opponent a full house.
- You are not drawing to the best hand. With a king-high flush draw, you lose to whoever holds the ace of that suit.
- Your opponent is drawing to the same cards. When two players share a flush draw, one player’s out is the other player’s disaster.
In practice the answer is not precise arithmetic but knocking a card or two off in your head before you compare with the price. That is more useful than working to two decimal places.
When you do not need to count
Not every hand needs the maths. Skip it when:
- You already hold a strong made hand — the question is how to get value, not whether to draw.
- The all-in your opponent has put in is far larger than your draw is worth; one look tells you it is not close.
- You have no outs at all. Missing is missing, and the question becomes whether you can bluff, not what your equity is.
For the full decision walked through end to end, see the pot odds example, which takes a single flush draw from flop to decision.
