Roll 2d20
Two twenty-sided dice shown side by side. In D&D you keep the higher (advantage) or the lower (disadvantage). Modiphius's 2d20 system, used in games like Star Trek Adventures and Conan, counts each die that rolls under a target.
Tap to add a die:
What a 2d20 is for
- Advantage (keep higher: 2d20kh1) and disadvantage (keep lower: 2d20kl1)
- Modiphius 2d20 system tests, where each die is checked against a target number
- Opposed rolls between two characters
Want more dice or a modifier? Edit the box, for example 2d20+2.
2d20 odds
Totals run from 2 to 40 and bunch in the middle. Average 21.0.
246810121416182022242628303234363840
| Total | Exactly | At least |
|---|---|---|
| 2 | 0.25% | 100.00% |
| 3 | 0.50% | 99.75% |
| 4 | 0.75% | 99.25% |
| 5 | 1.00% | 98.50% |
| 6 | 1.25% | 97.50% |
| 7 | 1.50% | 96.25% |
| 8 | 1.75% | 94.75% |
| 9 | 2.00% | 93.00% |
| 10 | 2.25% | 91.00% |
| 11 | 2.50% | 88.75% |
| 12 | 2.75% | 86.25% |
| 13 | 3.00% | 83.50% |
| 14 | 3.25% | 80.50% |
| 15 | 3.50% | 77.25% |
| 16 | 3.75% | 73.75% |
| 17 | 4.00% | 70.00% |
| 18 | 4.25% | 66.00% |
| 19 | 4.50% | 61.75% |
| 20 | 4.75% | 57.25% |
| 21 | 5.00% | 52.50% |
| 22 | 4.75% | 47.50% |
| 23 | 4.50% | 42.75% |
| 24 | 4.25% | 38.25% |
| 25 | 4.00% | 34.00% |
| 26 | 3.75% | 30.00% |
| 27 | 3.50% | 26.25% |
| 28 | 3.25% | 22.75% |
| 29 | 3.00% | 19.50% |
| 30 | 2.75% | 16.50% |
| 31 | 2.50% | 13.75% |
| 32 | 2.25% | 11.25% |
| 33 | 2.00% | 9.00% |
| 34 | 1.75% | 7.00% |
| 35 | 1.50% | 5.25% |
| 36 | 1.25% | 3.75% |
| 37 | 1.00% | 2.50% |
| 38 | 0.75% | 1.50% |
| 39 | 0.50% | 0.75% |
| 40 | 0.25% | 0.25% |
Roll history
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Questions people ask
Is 2d20 the same as advantage?
Advantage rolls 2d20 and keeps the higher one; it does not add them. Use 2d20kh1 in notation, or the d20 page's Advantage button.
What does 2d20 added together average?
21, ranging from 2 to 40 with a triangle-shaped distribution peaking at 21.