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Reference

The Dice Library

Everything worth knowing about dice, written to be read once and referred back to. Each article can be rolled as you read it, because a mechanic explained is worth less than a mechanic demonstrated.

  1. Dice Notation Explained

    What 2d6, 4d6kh3 and 1d20+7 actually mean, and how to read any dice expression you come across.

  2. The Types of Dice

    The seven dice in a standard polyhedral set, what each one is for, and which of the unusual dice are worth owning.

  3. How to Read a D4

    The four-sided die has no top face, which is why it confuses everyone at first. Here is how to read both kinds.

  4. How to Read Percentile Dice

    Two ten-sided dice make a number from 1 to 100. Here is how they combine, including the 00 case.

  5. How Dice Are Made, and Why It Matters

    Injection moulding, sanding and the tiny manufacturing details that make a physical die very slightly unfair.

  6. What Randomness Actually Means

    True randomness, pseudorandomness and why a run of bad rolls feels rigged when it is not.

  7. A Short History of Dice

    From knucklebones to the twenty-sided die, by way of a Roman gambling ban and an Egyptian board game.

  8. Why Dice Feel Unfair

    Streaks, clustering and the gambler's fallacy. The maths behind the feeling that your dice hate you.

Looking for a single term?

The glossary defines every piece of dice vocabulary in a sentence, and links each one to somewhere you can try it.

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