Dice Rollers
Roll With Advantage or Disadvantage
Roll two d20 and keep the higher or the lower, with both dice shown so the table can see the roll.
Roll With Advantage or Disadvantage
Advantage · kept 18
Keep which die
How to use the advantage roller
- Choose advantage to keep the higher d20, or disadvantage to keep the lower.
- Add your modifier, and set a DC to have the roller call success or failure.
- Press Roll two d20. Both dice show, with the kept one highlighted.
The exact numbers behind the roll
Rolling twice and keeping one die changes the odds in a precisely known way. The kept die averages 13.825 with advantage and 7.175 with disadvantage, against 10.5 for a single d20. What that means for hitting a target number:
| Roll needed | Single d20 | With advantage | With disadvantage |
|---|---|---|---|
| 5+ | 80% | 96.00% | 64.00% |
| 11+ | 50% | 75.00% | 25.00% |
| 15+ | 30% | 51.00% | 9.00% |
| 20+ | 5% | 9.75% | 0.25% |
The boost is biggest in the middle: a 50 percent check becomes 75 percent, while near certain and near impossible rolls barely move. That is why advantage is often described as worth about plus 3 to plus 5, most where the outcome hangs in the balance.
Criticals under advantage
A natural 20 needs at least one of the two dice to land on 20, which happens 9.75 percent of the time, nearly double the single die's 5 percent. A natural 1 under advantage needs both dice to fail together, collapsing to 0.25 percent. Disadvantage mirrors the pair exactly the other way. Over a long session those margins are the difference players feel.
Both dice on the table
This roller keeps both d20 visible with the kept die highlighted, the same transparency as rolling physical dice in the open, and the optional DC field calls success or failure so nobody re-does the arithmetic. For full damage rolls and stat blocks, the D and D dice roller carries the whole set.
Popular generators
Frequently asked questions
What is an advantage roll
You roll two twenty sided dice and keep the higher result. Disadvantage is the same but you keep the lower.
Are both dice shown
Yes. Both d20 results appear with the kept one highlighted, so a shared table can see the roll clearly.
Can I add a modifier
Yes. The modifier is added to the die you keep, matching a check such as a d20 with advantage plus 4.
How is the winner chosen
For advantage the higher die wins, for disadvantage the lower. On a tie both dice show the same value and either is kept.
Is it free
Yes, free and with no sign up. Every roll runs in your browser and nothing you enter leaves your device.
Related generators
- Dice Roller
- D&D Dice Roller
- Dice Notation Roller
- Custom Dice Roller
- Roll With Advantage or Disadvantage
- Yahtzee Dice Roller
- Farkle Dice Roller
- Flip a Coin
- Random Playing Card Generator
- Random Number Generator
Want more control? The D and D dice roller has the whole dice set, and the notation roller accepts 2d20kh1 directly.