Open-Ended Straight Draw
An open-ended straight draw is four consecutive cards that any of two ranks can complete into a straight. It has 8 outs, about 31.5% from flop to river.
An open-ended straight draw (often shortened to OESD) is four consecutive cards that can be completed into a straight by a card at either end. For example, holding 9♠ 8♠ on a flop of T♦ 7♣ 2♥ gives you T-9-8-7, which any jack or any six turns into a straight. With two ranks to hit and four cards of each rank left, you have 8 outs, twice as many as a gutshot.
Odds of completing it
| Situation | Chance to hit |
|---|---|
| Flop to turn (8 of 47 cards) | about 17.0% |
| Turn to river (8 of 46 cards) | about 17.4% |
| Flop to river (two cards) | about 31.5% |
With the rule of 2 and 4, 8 outs gives about 32% with two cards to come and 16% with one. As odds against for a single card on the turn, that is 39 to 8, or about 4.9 to 1.
When it is not really open-ended
- Ace at the end. J-Q-K-A can only be completed by a ten, and A-2-3-4 only by a five. These are one-way draws with 4 outs.
- Weak ends. Completing the low end of a straight can leave you beaten by a higher straight. Check what the completing card does for other hands.
- Flush boards. If the board also has two or three of one suit, some of your outs may give an opponent a flush.
Worked example
You hold 9♠ 8♠ on the button. The flop is T♦ 7♣ 2♥ and the pot is 60. Your opponent bets 30. You need to call 30 to win 90, so your pot odds require 25% equity. If you are guaranteed to see both the turn and the river, your 31.5% is enough. If you expect another bet on the turn, one card is only about 17%, so you also rely on implied odds, or on raising as a semi-bluff to win the pot right away.
The double gutshot
Some hands have 8 outs without four consecutive cards. Holding J♠ 9♠ on K♦ T♣ 7♥, a queen gives you K-Q-J-T-9 and an eight gives you J-T-9-8-7. This double gutshot has the same 8 outs and the same odds as an open-ended draw, and it is often better disguised.
Strategy tips
- Open-ended draws are good semi-bluffing hands, especially in position and with backdoor flush potential.
- Combined with a flush draw, an open-ender typically has 15 outs, about 54% with two cards to come.
- Don't pay large turn bets with only one card to come unless the price or the implied odds justify it.
Frequently asked questions
How many outs does an open-ended straight draw have?
Eight: four cards of each of the two ranks that complete the straight.
What are the odds of hitting an open-ended straight draw?
About 31.5% from the flop to the river, and about 17% with one card to come.
Is J-Q-K-A an open-ended straight draw?
No. Only a ten completes it because the ace cannot extend higher, so it has just 4 outs like a gutshot.
Related poker terms
- Outs — Outs are the unseen cards that will improve your hand to the likely winner. Counting them is the first step in working out your odds on a draw.
- Gutshot — A gutshot is a straight draw that needs one specific inside rank to complete, such as 9-8-6-5 needing a 7. It has 4 outs, about 16.5% from flop to river.
- Straight — A straight is five cards in consecutive rank of mixed suits, such as 9-8-7-6-5. It beats three of a kind and loses to a flush.
- Rule of 2 and 4 — The rule of 2 and 4 estimates your chance of hitting a draw: multiply outs by 4 on the flop (two cards to come) or by 2 on the turn (one card to come).
- Semi-Bluff — A semi-bluff is a bet or raise with a drawing hand that is behind now but can improve. It wins if opponents fold or if you hit your draw.
- Pot Odds — Pot odds compare the cost of a call to the size of the pot you could win, telling you the minimum equity you need for a call to be profitable.