About the eight-sided die
The d8 is an octahedron: eight equilateral triangles meeting four at each corner, like two square pyramids joined at their bases. It is one of the five Platonic solids, its opposite faces add up to 9, and each number has a 1-in-8 (12.5%) chance. The average roll is 4.5.
What the d8 is used for
In D&D the d8 is the workhorse damage die for one-handed weapons: the longsword (1d8, or 1d10 two-handed), rapier, battleaxe, warhammer, morningstar and longbow all deal 1d8. It is also the hit die for bards, clerics, druids, monks, rogues and warlocks, and the damage die of cantrips such as Sacred Flame.
A typical sword hit with a +3 Strength or Dexterity bonus is 1d8+3, averaging 7.5.
Two d8s and their odds
| Total | Ways | Chance | Odds | This or higher |
|---|---|---|---|---|
| 2 | 1 | 1.56% | 1 in 64 | 100% |
| 3 | 2 | 3.13% | 1 in 32 | 98.4% |
| 4 | 3 | 4.69% | 1 in 21.3 | 95.3% |
| 5 | 4 | 6.25% | 1 in 16 | 90.6% |
| 6 | 5 | 7.81% | 1 in 12.8 | 84.4% |
| 7 | 6 | 9.38% | 1 in 10.7 | 76.6% |
| 8 | 7 | 10.9% | 1 in 9.1 | 67.2% |
| 9 | 8 | 12.5% | 1 in 8 | 56.3% |
| 10 | 7 | 10.9% | 1 in 9.1 | 43.8% |
| 11 | 6 | 9.38% | 1 in 10.7 | 32.8% |
| 12 | 5 | 7.81% | 1 in 12.8 | 23.4% |
| 13 | 4 | 6.25% | 1 in 16 | 15.6% |
| 14 | 3 | 4.69% | 1 in 21.3 | 9.38% |
| 15 | 2 | 3.13% | 1 in 32 | 4.69% |
| 16 | 1 | 1.56% | 1 in 64 | 1.56% |
No d8? Make one from other dice
- d4 and a coin: roll the d4; on heads add 4. Every result from 1 to 8 is equally likely.
- From a d20 or d10: re-roll anything above 8 (on a d20, or 9 and 10 on a d10).