Dice Roll Simulator

Roll up to 10 dice of 4, 6, 8, 10, 12 or 20 sides, add a modifier, and get an instant result alongside the minimum, maximum and average for that roll. Tabletop players use it to sanity-check house rules, teachers lean on it to make probability tangible, and developers reach for it when balancing game mechanics, all without scrounging for physical dice.

Each roll draws a random face from 1 to the number of sides for every die, adds them up and applies the modifier. Alongside it the calculator shows the minimum (number of dice + modifier), the maximum (dice × sides + modifier) and the average, dice × (sides + 1) ÷ 2 + modifier. The chance of any particular total is the number of face combinations that produce it divided by the full count of possibilities, which is sides raised to the power of the number of dice; for two six-sided dice, 6 of the 36 combinations sum to 7.

Adding dice or sides balloons the sample space fast, and the distribution of sums stretches out into the familiar bell shape rather than staying flat. It is tempting to treat every total as equally likely, but with several dice the sums near the average dominate by a wide margin. The minimum, maximum and average are theoretical; any run of rolls, here or with physical dice, will scatter around the average with genuine short-term variance.