Probability

Probability, Bayes, combinations, dice, cards and odds.

• Bayes’ Theorem Calculator Updates a probability when new evidence comes in.
• Birthday Paradox Calculator The chance that two people in a group share a birthday.
• Card Probability Calculator The chance of drawing a number of chosen cards from a deck, without putting them back.
• Coin Flip Probability Calculator The chance of a given number of heads, and of a streak of heads, in a series of flips.
• Combination and Binomial Coefficient Calculator (nCr) The number of ways to choose items where order does not matter, including very large results.
• Conditional Probability Calculator The chance of A given B, from the probability of both and of each event.
• Dice Probability Calculator The chance of rolling a given total with any number of dice.
• Expected Value Calculator The probability-weighted average of a set of outcomes, with its variance.
• Factorial Calculator Factorials of whole numbers, including those far too large for ordinary arithmetic.
• Lottery Odds Calculator The odds of matching a lottery draw, from the numbers in play.
• Odds and Probability Calculator Converts odds to a probability, and a probability to odds.
• Odds Ratio Calculator The odds ratio from a 2×2 table of counts, with a confidence interval.
• Permutation Calculator (nPr) The number of ways to arrange items where order matters, including very large results.
• Probability Calculator The probability of an event, its complement, and the chance of it happening over repeated tries.
• Probability of Two Events Calculator The chance of A and B, A or B, exactly one or neither, for independent or mutually exclusive events.
• Relative Risk and Risk Difference Calculator The relative risk and risk difference between two groups, with confidence intervals.