Dice Probability Calculator

This tool gives the exact odds for a dice roll rather than an estimate from a simulation. Enter a roll such as 3d6 + 2 and a total you want to hit, and it returns the probability, the count of rolls that reach it, the average, the spread and the full distribution. Two other modes cover rolling several dice and keeping only the highest or lowest of them, as 4d6 keep 3 does, and rolling one die twice with advantage or disadvantage. Dice up to 100 sides and twenty at a time are handled, and the counts are kept as whole numbers so nothing is rounded before the answer.