Roll a d20
The twenty-sided die is the heart of Dungeons & Dragons and the wider d20 system — attack rolls, saving throws and ability checks all begin with a single d20. Roll one here, fairly, with no physical die to lose under the sofa. Everything runs locally in your browser.
d20
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The odds on d20
- Lowest
- 1
- Average
- 10.5
- Highest
- 20
| Result | Chance |
|---|---|
| 6 or more | 75% |
| 11 or more | 50% |
| 15 or more | 30% |
| exactly 20 | 5% |
Exact probabilities, not simulated. Want the full distribution and custom targets? Use the full dice roller.
FAQ
What is a d20 used for?
In D&D and most d20-system games you roll a d20 for nearly every check: roll high, add your modifier, and compare to a target number. A natural 20 is an automatic hit (and often a critical), while a natural 1 is an automatic miss.
Are these d20 rolls really random?
Yes. Each die uses your browser’s cryptographic random generator with rejection sampling, so every face has an exactly equal chance — no modulo bias, no loaded dice.
Does this dice roller run in my browser?
Yes. Every roll happens locally on your device — nothing is uploaded and it works offline once the page has loaded.
Need different dice, custom notation like 2d8+3, or a roll history? Use the full Dice Roller.