Free Dice Roller
Dice Roller rolls d4, d6, d8, d10, d12, d20 and d100 dice or standard RPG notation such as 3d6+2, 4d6dl1 or 2d20kh1, with exploding dice, re-rolls and Fudge dice. Rolls use your browser's cryptographic random generator, and for simple sums an odds panel shows the exact chance of each total for up to 200 dice.
- Dice:
- d4 to d100, d% and Fudge (dF)
- Notation:
- 3d6+2, keep/drop, exploding (!)
- Odds:
- Exact, up to 200 dice
- Price:
- Free
- Runs:
- Locally, in your browser
- Uploads:
- None: files never leave your device
- Account:
- Not needed
Quick answers
What dice notation is supported?
Standard RPG notation: NdX for N dice with X sides, plus or minus numbers, keep/drop (kh, kl, dh, dl), exploding dice (!), re-rolls (r), percentile (d%) and Fudge dice (dF).
Processed on your device: your files are never uploaded. How it works
Network activity in this tab
What this page has requested since you opened the site in this tab. An upload is any request that sends data: POST, PUT, PATCH or a request with a body.
No uploads: nothing has been sent from this page.
No network requests yet.
To see every request, open your browser's developer tools (Network tab).
How to use the Dice Roller
- Choose how many dice and click d4, d6, d8, d10, d12, d20 or d100.
- Or type a notation such as 3d6+2, 4d6dl1 (drop lowest) or 2d20kh1 (advantage) and press Roll.
- See every die, the total and your roll history.
- For simple sums, check the odds: average, range and the chance of rolling at least a target total.
Credits & open source
Our own code plus open-source libraries. Thank you to the people who make these projects.
- RPG Dice RollerDice notation parser and roller. © GreenImp Media Limited · MIT
- Random.jsUnbiased random number engines (used through RPG Dice Roller's browser-crypto engine). © Cameron Knight · MIT
- Math.jsExpression parser and math library with big-number support. © Jos de Jong and contributors · Apache-2.0
Web platform APIs used: Web Crypto.
Full license texts: third-party notices · all credits
Frequently asked questions
Are the rolls fair?
Yes. Every die uses your browser's cryptographic random generator with an unbiased method, never Math.random.
How are the probabilities calculated?
Exactly, not by simulation: the tool combines the faces of every die (a convolution) to get the chance of each possible total.