Poker Hand Probability Calculator
How rare is a royal flush, really? What are the actual odds of being dealt pocket aces? This educational tool reveals the fascinating mathematics behind poker hands. Understanding these probabilities is what separates casual players from those who truly comprehend the game's underlying structure.
Texas Hold'em Outs Calculator
Calculate your odds of improving your hand on the turn or river.
Pre-Flop Starting Hand Odds
Before the community cards are dealt, your starting hand is determined purely by probability. The mathematics are precise and unchangeable. According to PokerNews, understanding starting hand probabilities is the foundation of sound poker strategy.
Probability of Being Dealt Specific Starting Hands
Complete Poker Hand Probabilities
The odds of being dealt specific 5-card poker hands are calculated using combinatorics. There are exactly 2,598,960 possible 5-card combinations from a standard 52-card deck. These calculations, first formalized by mathematicians in the 18th century, form the basis of poker hand rankings. The Mathematics Is Fun probability guide explains the underlying combinatorial principles.
Royal Flush
Straight Flush
Four of a Kind
Full House
Flush
Straight
Three of a Kind
Two Pair
Complete Probability Reference Table
This comprehensive table shows every standard poker hand ranking with precise mathematical probabilities. These figures are based on the total number of possible 5-card combinations (2,598,960) from a standard 52-card deck, as documented by the Encyclopedia Britannica.
| Hand | Combinations | Probability | Odds (1 in X) |
|---|---|---|---|
| Royal Flush | 4 | 0.000154% | 649,740 |
| Straight Flush | 36 | 0.00139% | 72,193 |
| Four of a Kind | 624 | 0.024% | 4,165 |
| Full House | 3,744 | 0.144% | 694 |
| Flush | 5,108 | 0.197% | 509 |
| Straight | 10,200 | 0.392% | 255 |
| Three of a Kind | 54,912 | 2.11% | 47 |
| Two Pair | 123,552 | 4.75% | 21 |
| One Pair | 1,098,240 | 42.26% | 2.4 |
| High Card | 1,302,540 | 50.12% | 2.0 |
Texas Hold'em: The 7-Card Advantage
Texas Hold'em changes these probabilities significantly because players choose the best 5 cards from 7 (2 hole cards + 5 community cards). This dramatically increases the chances of making strong hands. Research from the Carnegie Mellon University AI research program has extensively analyzed these probabilities in their poker AI systems.
7-Card Hand Probabilities (Texas Hold'em)
Note: These 7-card probabilities are about 20x higher for royal flushes compared to 5-card draw, which is why Hold'em produces more dramatic showdowns.
Understanding Outs and Drawing Odds
In Texas Hold'em, "outs" are the cards that will improve your hand. Knowing how many outs you have and the probability of hitting them is essential for making mathematically sound decisions. The Card Player magazine provides extensive resources on calculating outs in various situations.
Common Drawing Situations
| Draw Type | Outs | Turn % | River % | Both Cards % |
|---|---|---|---|---|
| Pocket pair to set | 2 | 4.3% | 4.3% | 8.4% |
| Gutshot straight | 4 | 8.5% | 8.7% | 16.5% |
| Two overcards | 6 | 12.8% | 13.0% | 24.1% |
| Open-ended straight | 8 | 17.0% | 17.4% | 31.5% |
| Flush draw | 9 | 19.1% | 19.6% | 35.0% |
| Flush + gutshot | 12 | 25.5% | 26.1% | 45.0% |
| Flush + open-ended | 15 | 31.9% | 32.6% | 54.1% |
When Probability Meets Reality
Understanding poker probability helps explain some of the most dramatic stories in gambling history. The same mathematical principles that govern poker hands also underlie how casinos track player behavior and identify statistical anomalies.
The MIT Blackjack Team succeeded by exploiting probability in blackjack, and similar mathematical advantages exist in poker. Unlike blackjack, where the house always has an edge, poker is a game where skilled players can have positive expected value because they're playing against other players, not the house.
This is why the biggest wins in gambling history often involve games with player-vs-player elements or progressive jackpots where the mathematics occasionally favor the player. Understanding these probabilities doesn't guarantee winning, but it does explain why certain outcomes are remarkable and others are routine.
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