How to use it
- Choose 1 to 10 dice and a die type: d4, d6, d8, d10, d12 or d20. A regular six-sided die is selected to start.
- If your game adds or subtracts a fixed number, enter it as the modifier. Leave it at 0 to add nothing.
- Press Roll, or press Space or Enter, to see each die, the total and your roll history.
Reading dice notation
The history shows notation like 2d6+3. The first number is how many dice, the number after d is how many sides, and the last part is the modifier. So 2d6+3 means roll two six-sided dice and add 3 to the total.
Why totals bunch up in the middle
Each face of a single die is equally likely, but totals of several dice are not. With two six-sided dice there are 36 possible combinations: 6 of them add up to 7, the most of any total, while 2 and 12 have only one each. That is why middle totals come up often and extreme totals rarely.
Good for
- Board games when the dice have gone missing
- Tabletop role-playing games that need d20s, d12s and other polyhedral dice
- Deciding turn order, picking a forfeit, or probability lessons
How the result is decided
Each die is decided with a random number from your browser's crypto.getRandomValues. Values from the uneven tail of the range are thrown away and drawn again (rejection sampling), so dividing by the number of sides adds no modulo bias. The rolling animation lasts under 0.6 seconds and is skipped when your device is set to reduce motion.