How to roll dice online
- Number of dice — how many to roll at once, from 1 to 100.
- Sides per die — the standard six-sided cube (d6), or the polyhedral dice used in role-playing games: d4, d8, d10, d12, d20 and the d100 percentile die.
- Modifier — a number your game adds to or subtracts from the total, such as +5 for a skilled character. Leave it at 0 for plain rolls.
- Press Roll. You see the total, every individual die, and the odds of what you rolled.
The settings are remembered on this device, so on game night you only press Roll. Copy link saves a setup such as 4d6 or 1d20 + 3 to share with the group.
Dice notation
Games write dice as NdS+M: N dice with S sides each, plus a modifier M. “2d6” is two ordinary dice added together; “1d20+5” is one twenty-sided die plus five; “3d8−1” is three eight-sided dice minus one. A “d100” or percentile roll gives a number from 1 to 100 — tabletop players often make it from two ten-sided dice, one for tens and one for units.
Why middle totals come up most
A single fair die is flat: on a d6 each face has a 1 in 6 (16.7%) chance. Add dice together and the totals stop being equal, because more combinations make the middle numbers. With two dice there is only one way to roll 2 (1 + 1) but six ways to roll 7. That is why 7 is the most common total in board games such as Catan, and why 2 and 12 are rare:
| Total of 2d6 | Ways out of 36 | Chance |
|---|---|---|
| 2 | 1 | 2.8% |
| 3 | 2 | 5.6% |
| 4 | 3 | 8.3% |
| 5 | 4 | 11.1% |
| 6 | 5 | 13.9% |
| 7 | 6 | 16.7% |
| 8 | 5 | 13.9% |
| 9 | 4 | 11.1% |
| 10 | 3 | 8.3% |
| 11 | 2 | 5.6% |
| 12 | 1 | 2.8% |
The calculator computes this distribution exactly for any combination, up to 100 dice of up to 100 sides, so “Chance of this total or higher” answers questions like “what are my odds of rolling 15 or more on 3d6?” (9.3%). The average of one die is (1 + S) ÷ 2 — 3.5 for a d6 and 10.5 for a d20 — and the average of a sum is that times the number of dice, plus the modifier.
Common rolls
- Board games: 1d6 or 2d6. If your physical dice go missing, this page replaces them exactly.
- Role-playing games: 1d20 for checks and attacks; damage dice such as 1d8 or 2d6. For advantage, roll 2d20 and keep the higher die; for disadvantage keep the lower one — both dice are listed under the total.
- Ability scores: many players roll 4d6 and drop the lowest die, six times.
- Teaching probability: roll 100 dice to watch the average approach 3.5, then compare the odds table with the frequencies you see.
For one number in any range, use the random number generator; for a yes-or-no, flip a coin.
Frequently asked questions
Are these dice fair?
Yes. Each die uses your browser’s cryptographically secure random generator with rejection sampling, so every face has exactly the same chance. Physical dice can be slightly unbalanced by drilled pips or rounded edges; these cannot.
What is the most common roll with two dice?
Seven. Six of the 36 combinations add up to 7 (1+6, 2+5, 3+4, 4+3, 5+2, 6+1), a 16.7% chance. Totals of 2 and 12 each have only one combination, 2.8%.
How do I roll with advantage?
Set 2 dice with 20 sides and roll; use the higher of the two values listed under “Each die.” For disadvantage use the lower one. Add your modifier yourself, or set it and subtract the dropped die mentally.
Can I roll a negative modifier?
Yes. Type a negative number such as −2 in the modifier box; the total, the minimum, the maximum and the odds table all shift by it.
Last updated: October 14, 2026