Craps is one of the most mathematically interesting casino games, where understanding probability is essential to making informed betting decisions. The game centers on the rolling of two six-sided dice, which creates a foundation for calculating precise odds and evaluating bet values.
The Basics of Dice Combinations
With two dice, there are 36 possible outcomes (6 × 6). However, the sum totals range from 2 to 12, and each sum has a different probability. For example, rolling a 7 is the most likely outcome with six possible combinations: (1,6), (2,5), (3,4), (4,3), (5,2), and (6,1). This fundamental fact shapes most craps betting strategies, as the 7 is both a winning and losing roll depending on the game phase.
Understanding these probabilities allows players to evaluate which bets offer better mathematical value. A 2 or 12 (snake eyes or boxcars) each has only one combination out of 36, making these the rarest outcomes. A 6 or 8 each has five possible combinations, making them the second most likely outcomes after 7.
House Edge and Betting Odds
The craps table offers numerous betting options, each with different odds and house advantages. The Pass Line bet, one of the most popular starting wagers, has a house edge of approximately 1.4%. This relatively low house edge is achieved when the true probability of rolling the point number before rolling a 7 is calculated against the payouts offered.
Come bets and Don't Come bets mirror Pass Line and Don't Pass Line mechanics, providing similar mathematical profiles. Field bets, while exciting, carry a higher house edge of around 2.78% to 5.56%, depending on the specific casino rules regarding 2 and 12 payouts.
Point Probability and Winning Strategies
After a point is established in craps, the probability of rolling that number before rolling a 7 varies based on what the point number is. If the point is 6 or 8, the probability of rolling the point before a 7 is approximately 48.5%, while rolling a 7 first has about a 51.5% probability. This explains why backing up your point with odds bets at favorable payouts (6-to-5 for 6 or 8) becomes mathematically sound.
Points of 5 or 9 have roughly 40% probability of hitting before a 7, while points of 4 or 10 have about 33% probability. Understanding these percentages helps determine which points offer the best odds for supporting bets.
Table Etiquette and Responsible Play
Beyond mathematics, craps demands adherence to specific table conventions. Never touch the dice with two hands, always throw toward the back wall, and avoid mentioning the number 7 during rolls or using words like "snake eyes" that may be considered unlucky by other players. These customs create a respectful gaming environment.
Remember that despite favorable mathematics on certain bets, the house always maintains a mathematical edge. Bankroll management, setting loss limits, and understanding that dice outcomes are random and independent events are crucial for responsible gaming.