Flop Odds: How Often You Flop a Set, Flush, Straight or Pair

Most Hold’em hands are won or lost on the flop. Knowing how often each starting hand connects tells you which hands are worth calling a raise with, and which ones only look pretty. Every number below is exact — worked out by counting all 19,600 possible flops, not by simulation.

The quick reference

You hold	You flop	Chance
Any pocket pair	A set or better	11.8% (about 1 in 8.5)
Any pocket pair	Quads	0.2% (1 in 408)
Any pocket pair	A full house (set + a pair on board)	0.7% (1 in 136)
Two unpaired cards	At least one pair using your cards	32.4% (about 1 in 3)
Two unpaired cards	Two pair using both cards	2.0% (1 in 49)
Two unpaired cards	Trips (one of your cards + a pair on board)	1.3% (1 in 74)
Two suited cards	A flush	0.8% (1 in 119)
Two suited cards	A flush draw (two of your suit on board)	10.9% (1 in 9)
Two suited cards	A backdoor flush draw (one of your suit)	41.6%
Connectors like 7-6 or J-T	A straight	1.3% (1 in 77)
Connectors like 7-6 or J-T	An open-ended or double-gutshot draw	9.7%
Connectors like 7-6 or J-T	A gutshot	16.8%

A few numbers are worth memorising: pairs flop a set about 1 time in 8, unpaired hands pair up about 1 time in 3, and suited hands flop a flush draw about 1 time in 9.

Where the numbers come from

After you’re dealt two cards, 50 remain, and there are 19,600 different three-card flops. Each probability is just the number of flops that give you a hand divided by 19,600.

Flopping a set with a pocket pair. Two cards of your rank are left. The chance that none of them hits is 48/50 × 47/49 × 46/48 = 88.2%, so you flop a set or better 11.8% of the time.

Pairing an unpaired hand. With A-K, six cards (three aces and three kings) pair you. The chance of missing all three flop cards is 44/50 × 43/49 × 42/48 = 67.6%, so you pair at least one card 32.4% of the time. The other two times in three, you have ace-high — which is why ace-king needs a plan when it misses.

Flopping a flush. Eleven cards of your suit are left: 11/50 × 10/49 × 9/48 = 0.84%. Suited cards make a flush far more often by the river, but on the flop it’s rare.

What it means for hand selection

Pocket pairs: set mining needs a price

A small pair usually needs a set to win a big pot, and it only flops one about 1 time in 8.5. Calling a raise to “set mine” therefore only works when you can win much more when you hit.

A common rule of thumb is that both players should have at least 15–20 times the call left in their stacks. If someone raises to 6 and you’ll only win another 40 when you flop a set, you’re losing money. If they have 200 behind and will pay you off with an overpair, the call is fine. That extra money is your implied odds.

Suited cards: less than you’d think

Suited cards look strong, but you flop a flush just 0.8% of the time and a flush draw 10.9% of the time. Being suited adds roughly 2–4% of equity against most hands. That’s worth having — it’s why suited hands open earlier on preflop charts — but it doesn’t make a weak hand strong.

Connectors: lots of draws, few made hands

A hand like 7♠6♠ flops a made straight only 1.3% of the time, but some kind of straight draw more than a quarter of the time (9.7% + 16.8%), and a flush draw another 10.9%. That’s why connectors play best in position and deep, where you can realise the value of those draws. The position lesson explains why.

Big cards: you’ll miss two times in three

A-K, A-Q and K-Q all pair up only about a third of the time. The rest of the time they’re relying on fold equity, a good continuation bet or high-card value. Their strength is that when they do pair, it’s usually top pair with a good kicker.

How often you flop nothing

It’s worth knowing how often you completely miss:

You hold	Chance of no pair and no draw on the flop
Suited connectors (e.g. 7♠6♠)	37.6%
Offsuit big cards (e.g. A♠K♥)	56.0%

“No draw” here means no pair, no four-card flush draw and no straight draw — backdoor draws aside. Suited connectors miss less often than big offsuit cards, but when they hit they usually make a draw, not a strong made hand. Big cards miss more often, but hit harder.

Two worked examples

Set mining. You hold 4♣4♦ in the cutoff and a player raises to 3 big blinds in front of you. You both have 100 big blinds. Your implied odds are big — 97 more big blinds to win — so calling to try to flop a set (11.8%) is reasonable, especially in position.

Now make the stacks 25 big blinds, as often happens in tournaments. There’s only 22 big blinds left to win when you hit, which isn’t enough. Here the choice is usually shove or fold, not call — see push/fold charts.

Suited connectors multiway. You hold 8♥7♥ on the button and three players limp. You flop a straight draw or flush draw more than a third of the time, and when you hit, big hands pay you off in multiway pots. This is the spot where speculative hands earn their money.

Quick questions

What are the odds of being dealt a pocket pair? 5.9%, or 1 in 17. A specific pair, like pocket aces, is 1 in 221.

What are the odds of flopping a set with two players holding pairs? Each player still flops a set 11.8% of the time. Both flopping a set at once is rare — under 1% — which is why set-over-set is such a memorable cooler.

Does it matter which pair or which connectors? Not for these odds. 2-2 flops a set as often as A-A, and 5-4 flops a straight as often as J-T. What changes is how good that hand is when you make it.

How do I work out the odds after the flop? Count your outs and use the poker outs chart or the rule of 2 and 4.

Run any hand against another in the odds calculator, and practise counting draws in the outs trainer. The full maths is in Pot Odds and Outs.

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