Gutshot Straight Draw Odds: 4 Outs Math

Flop → River

16.47%

Turn Card

8.51%

River Card

8.70%

Gutshot + 2 overcards — 10 outs

AK on a Q-J-3 board has a gutshot to the 10-straight plus 6 overcard outs to make top pair. Combined ~32% equity flop-to-river — call up to 1/2 pot.

Gutshot + flush draw — 12 outs

T9♣ on 7♣-8♦-2♣ has a gutshot to the 6 plus a flush draw. 12 outs = ~45% equity — a near-favorite over top pair.

Implied odds + deep stacks

Calling a 1/3 pot flop bet 200bb deep with a gutshot is fine when the straight is well-disguised and opponent will pay off the river.

Semi-bluff with fold equity

Raising a gutshot with 30%+ fold equity is +EV. The 16.5% equity when called combined with folds when villain misses makes this a standard line on dry boards.

What are the odds of hitting a gutshot straight draw?

A gutshot has exactly 4 outs and the flop-to-river probability of completing it is 16.47%. The Rule of 4 & 2 estimates 4 × 4 = 16%, which is within 0.5 percentage points of the exact figure. On the turn alone, the gutshot hits 8.51% of the time; on the river alone, 8.70%. These are the lowest single-card hit rates of any standard draw worth playing.

How many outs does a gutshot have?

A gutshot straight draw has 4 outs. The 'inside' card needed to complete the straight comes in only one rank, and only 4 cards of that rank exist in a 52-card deck. For example, holding 7-8 on a J-9-2 flop, you need a 10 to complete 7-8-9-10-J. There are 4 tens in the deck, so 4 outs.

What pot odds do I need to call a gutshot?

On the river, you need at least 10.5-to-1 pot odds to call profitably with a pure gutshot (no other equity). On the turn deciding turn-only, the threshold is 10.75-to-1. If you're calling on the flop with two cards to come (the turn and river both available), you can use 5.07-to-1 — but this only applies if you expect to see the river for free. Most flop calls require 5-to-1 plus implied odds.

Is a gutshot a good draw?

A bare gutshot is generally too weak to call large bets. With 4 outs and 16.5% equity flop-to-river, you need a half-pot bet to give you 25% pot odds — and you have 16%. Gutshots become playable when combined with overcards (gutshot + 2 overs = ~10 outs, 32%), a flush draw (gutshot + flush draw = 12 outs, 45%), or a backdoor flush draw on dry boards.

What's the difference between a gutshot and an OESD?

A gutshot is an 'inside' straight draw with 4 outs (one rank completes it). An OESD (open-ended straight draw) has 8 outs because two different ranks complete it — one on each end. OESD hits 31.5% by the river vs the gutshot's 16.5%. The OESD is twice as strong because there are two suits' worth of outs (8 cards) instead of one rank's worth (4 cards).

Should I semi-bluff with a gutshot?

Yes, on selective boards. A pure gutshot has only 4 outs (16% equity flop-to-river), which is too low to bluff with the expectation of being called. However, gutshots become strong semi-bluff candidates when paired with other equity sources: a gutshot + flush draw (12 outs, 45%) is one of the strongest semi-bluff hands in poker. The math: you need ~30% fold equity to make a semi-bluff with a bare gutshot profitable.

How do you spot a gutshot draw?

Look at your hole cards and the board for any straight that's missing exactly one rank in the middle. For example, with 7-8 in your hand and 5-9-K on the flop, the straight is 5-6-7-8-9 — missing the 6. That's a gutshot. With 7-8 on a J-9-2 flop, the straight is 7-8-9-10-J — missing the 10. Always count the cards needed to make a 5-card straight, then identify the gap.