Rolling dice, and reading the notation

What this tool does

The Dice Roller rolls any standard die — d4, d6, d8, d10, d12, d20 and d100 — or any combination written in dice notation. It shows the total, every individual die, and a history of your recent rolls. It all runs in your browser.

The standard dice

Tabletop games use polyhedral dice named by their number of sides: a d6 is the familiar cube, a d20 is the icosahedron central to Dungeons & Dragons, and a d100 (often two d10s) gives a percentage. Each die is equally likely to land on any face.

Dice notation

Notation is a compact way to describe a roll: 2d6+3 means "roll two six-sided dice and add three". The pieces are:

• Number of dice — the value before the d (2 in 2d6).
• Sides — the value after the d (6 in 2d6).
• Modifier — an optional +N or -N added to the total.

You can chain terms too, like 1d20+1d4+2.

Are the rolls fair?

Yes. The roller draws randomness from crypto.getRandomValues and uses rejection sampling so there's no modulo bias — every face has exactly equal odds, just like physical dice in good condition.

How to use it

1. Open the Dice Roller.
2. Tap a die (d6, d20, …) for a quick single roll.
3. Or type notation such as 4d6 or 2d20-1 and press Roll.
4. Read the total and the individual dice; check the history for previous rolls.

Nothing is uploaded

Every roll happens locally in your browser — your rolls and history never leave your device.

FAQ

What does dice notation like 2d6+3 mean?

Roll two six-sided dice and add three to the total.

Are the rolls actually random?

Yes — they use the browser's cryptographic randomness with rejection sampling for unbiased results.

Is anything uploaded?

No — it all runs in your browser.

Ready to try it? Open the Dice Roller →