Reading dice notation
3d6+2 means roll three six-sided dice, add them, add two. d20 is a single twenty-sided die. 2d8-1 subtracts. It is the notation every tabletop rulebook uses, and it is accepted here directly rather than making you fill in fields.
Why several dice are not the same as one big one
3d6 and 1d18 both range from roughly 3 to 18, and they behave completely differently. A single die is flat — every result equally likely. Three dice cluster around the middle: 10 and 11 come up about six times as often as 3 or 18.
That is why systems use multiple dice for anything meant to be predictable and a single d20 for anything meant to be dramatic.
Each roll is independent
Dice have no memory. Four ones in a row does not make a five more likely next time, however strongly it feels that way — the gambler’s fallacy is one of the most robust illusions in probability. Every roll here uses the system’s cryptographic random source, so the sequence is genuinely independent.
Frequently asked questions
What does 3d6+2 mean?
Roll three six-sided dice, add the results, then add two. It is standard tabletop notation and can be typed directly.
Is 3d6 the same as 1d18?
No. A single die is flat; three dice cluster around the middle, where 10 and 11 come up roughly six times as often as the extremes.
Are the rolls really random?
They use the operating system’s cryptographic random source. Each roll is independent — a run of low numbers does not make a high one more likely.
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