What are the odds of hitting a gutshot?
A gutshot (inside straight draw) completes 16.47% of the time by the river and 8.51% on the turn.
Probability
16.47%
about 1 time in 6.1
on the next card
8.51%
Exact. Hypergeometric probability over the 47 unseen cards.
One rank fills the straight, and there are four of it: four outs. 8.51% on the turn, 16.47% by the river — about one time in six.
Gutshots are rarely worth chasing on their own odds, but they add up: a gutshot with two overcards is ten outs, and a gutshot with a flush draw is twelve.
- Outs to a straight4
- Unseen cards on the flop4752 − 2 − 3
- Ways to miss twice903C(43, 2) = 903
- Total two-card run-outs1,081C(47, 2) = 1081
- Probability of hitting by the river16.47%1 − 903 / 1081
- Rule of 4 estimate16.00%4 × 4%
- On the turn alone8.51%4 / 47
- Rule of 2 (turn)8.00%4 × 2%
Try it
Change any card; the numbers recompute from the same engine that produced the answer above.
Your hand
Board
Hand now
Ace High
Outs
10
of 47 unseen
By the turn
21.3%
10 / 47
By the river
38.4%
two cards to come
The 10 highlighted cards are your outs.
What you’re drawing to
- Gutshot straight draw4 outs
- Two overcards6 outs
Pairing an overcard makes top pair, which is not always the best hand.
Shortcut vs. exact
| Cards to come | Rule of 2/4 | Exact | Gap |
|---|---|---|---|
| Turn only | 20% | 21.28% | −1.28 pts |
| Turn and river | 40% | 38.39% | +1.61 pts |