Randomantic How to use the dice roller
- Pick a die type — D6 is the standard board game die; D20 is the RPG favorite.
- Choose how many dice to roll at once (up to 20).
- Click Roll the dice — each die result is shown along with the total.
When a virtual dice roller beats real dice
Real dice go missing, fall off tables, and can't be rolled quietly on a bus. A virtual roller is always in your pocket: perfect for board games with lost dice, D&D and other tabletop RPGs, classroom probability lessons, and quick decisions ("roll a D6, odd we stay in, even we go out"). Rolling many dice at once with an instant total also speeds up games like Yahtzee or damage rolls with big dice pools.
Reading dice notation
Tabletop rules are written in a shorthand worth knowing: 2d6 means roll two six-sided dice and add them, 1d20 is a single twenty-sided die, and 3d6+2 means roll three six-sided dice, total them, then add two. The number before the d is how many dice, the number after is how many sides. Set the die type and the count on this page and the total is worked out for you, which is the slow part when you are rolling eight dice for damage.
2d6 and 1d12 are not the same thing
Both give you a number from 2 to 12 — but they are completely different distributions, and this trips up a lot of people designing their own games. A single twelve-sided die is flat: every result is equally likely. Two six-sided dice are a bell curve: there are six ways to roll a 7 and only one way to roll a 12, so 7 comes up six times as often as either extreme. If you want results clustered around the middle with rare dramatic highs and lows, roll more dice with fewer sides. If you want every outcome equally likely, roll one die with more sides.
Advantage, disadvantage, and dropping dice
Modern RPGs lean on rolling multiple dice and ignoring some of them. Advantage is rolling 2d20 and taking the higher — worth roughly a +5 bonus on average, and much more than that in the middle of the range. Disadvantage takes the lower. Character generation often uses 4d6 drop lowest, which is why rolled stats skew high compared to a straight 3d6. Roll the dice you need here and apply the rule yourself; the individual results are shown alongside the total for exactly that reason.
Are virtual dice fairer than real ones?
Usually, yes. A physical die is a manufactured object: the pips are drilled out, so the six face is very slightly lighter than the one face, and cheap dice have rounded edges and air bubbles that bias them further. This is why casinos use sharp-edged precision dice with flush, painted pips, and replace them regularly. A software roll has no geometry to be wrong — every face is exactly as likely as every other. What it loses is the physical ritual, which for a lot of players is the whole appeal, so this is a tool for when the dice are lost or the table is a bus.
In the classroom
Dice are the cheapest probability lesson there is. Rolling 2d6 fifty times and tallying the results produces a visible bell curve, and the gap between what students predict and what they get is where the learning happens. Rolling many dice at once here makes the sample sizes large enough to be convincing in a single lesson, rather than a term of hand-tallying.
For a plain number outside the standard die sizes, use the random number generator; to decide turn order before the game starts, shuffle the players with the list randomizer.