Here are some basic probabilities that you should know:
Flush Probabilities
Probability of being dealt suited cards: 23.5%
Probability of flopping a flush when holding two suited cards: 0.8%
Probability of flopping a flush draw when holding two suited cards: 10.9%
Probability of hitting a flush draw (both turn/river, needing one card to hit): 35%
Straight Probabilities
Probability of hitting an open-ended straight draw (i.e. 4 straight cards, need one on either end to hit on turn or river): 31.5%
Probability of hitting a gutshot draw (inside straight draw) on turn or river: 16.5%
Pocket Pair Probabilities
Probability of being dealt a pocket pair: 5.9%
Probability of hitting a three of a kind or quads at the flop when you hold a pocket pair: 11.8%
Probability of being dealt AA: 0.45%
Unpaired Hole Cards Probabilities
Probability of making a pair with one of your hole cards (example: hitting an ace or a king if you hold AK): 32.4%
Probability of hitting two pair on the flop with each of your hole cards (example: hitting both an ace and a king on the flop, when holding AK): 2%
Ace Probabilities
Probability that at least one of your hole cards is an ace: 14.9%
Probability of no one holding an ace, assuming you do not have an ace, by the number of opponents. Note: this can be used for any card (because the chances of you being dealt an ace or a king is exactly the same).:
84.5%
70.9%
59.0%
48.6%
39.7%
32.1%
25.6%
20.1%
15.6%
Probability someone else does not have an ace, assuming you do have an ace, by total number of opponents:
88.2%
77.5%
67.7%
58.6%
50.4%
43.0%
36.4%
30.5%
25.3%
