How to use
- Choose the number of dice (1–20) and the sides (d4 to d100). A regular die is a d6.
- Press Roll to see each die and the total right away.
- For tabletop RPGs, add a modifier to the total, as in
2d6+3. - The last 20 rolls are kept in the history, which you can copy in one go.
Dice notation and odds
3d6+2 means “roll three six-sided dice and add 2 to the sum”: the first number is how many dice, the number after d is the sides, and the last part is the modifier.
| Roll | Range | Average | Notes |
|---|---|---|---|
| 1d6 | 1–6 | 3.5 | each face 1 in 6 |
| 2d6 | 2–12 | 7 | 7 is the most likely total, 6 in 36 |
| 1d20 | 1–20 | 10.5 | each face 5% |
| 3d6+2 | 5–20 | 12.5 | |
| 1d100 | 1–100 | 50.5 | percentile checks |
The average of one die is (sides + 1) ÷ 2. For several dice, multiply by the number of dice and add the modifier.
Examples
- In a board game, rolling 2d6 and getting 4 and 3 gives a total of 7.
- An attack roll of 1d20+5 that lands on 14 totals 19.
- For a “30% chance” check with d100, a result of 1–30 counts as success.
Is it fair?
Every die is rolled with the browser’s crypto.getRandomValues(), using rejection sampling so no face comes up more often because of remainder arithmetic. Earlier rolls never influence later ones, so streaks of the same number are ordinary chance.
Things to keep in mind
- If your device has reduced motion turned on, the dice update without the roll animation.
- History disappears when you close or refresh the page.
- To draw numbers from a custom range or without repeats, use the random number generator.
FAQ
Why does 7 come up most often with 2d6?
Six of the 36 possible combinations add up to 7 (1+6, 2+5, 3+4, 4+3, 5+2, 6+1) — more than any other total — so its chance is 1 in 6.
Does the d10 go from 0 or 1?
Here it rolls 1 to 10. Some physical d10s are numbered 0–9; if your game uses 0, read a 10 as 0.