D8 Dice Roller
An octahedron, which is two square pyramids glued base to base. It has eight triangular faces and a surprisingly long roll, so it likes to leave the table and end up under the sofa. Of the seven standard dice it is probably the one people handle without ever thinking much about it.
Press Roll to throw the dice.
Press Space to roll again. Type notation like 2d6+3 or 4d6dl1 straight into the box.
Recent rolls
- No rolls yet.
A d8 has 8 faces numbered 1–8. On a fair die every face is equally likely, so any single result comes up 12.5% of the time. Rolls run from 1 to 8, the average is 4.5, and the standard deviation is 2.29. The shape it is built from is the octahedron.
- Minimum
- 1
- Maximum
- 8
- Mean
- 4.5
- Median
- 4.5
- Std deviation
- 2.29
- Chance per face
- 12.5%
d8 probability
One die is flat. There is no curve and no middle to aim for, because each face has exactly one way to come up out of 8 possible results, so nothing is more likely than anything else. Add a second die and that changes immediately: totals start piling up in the middle. The dice probability guide works through why.
| Total | Ways | Probability | This or lower |
|---|---|---|---|
| 1 | 1 | 12.5% | 12.5% |
| 2 | 1 | 12.5% | 25% |
| 3 | 1 | 12.5% | 37.5% |
| 4 | 1 | 12.5% | 50% |
| 5 | 1 | 12.5% | 62.5% |
| 6 | 1 | 12.5% | 75% |
| 7 | 1 | 12.5% | 87.5% |
| 8 | 1 | 12.5% | 100% |
When you'd roll a d8
The d8 is the middle weight. It gives more range than a d6 without the wild swing of a d12, which is why so many weapon and healing effects settled on it. Outside role-playing it handles any eight-way choice cleanly: eight compass points, eight players in a bracket, eight tracks in a shuffle. Roll it in a tray unless you enjoy crawling around the floor.
Common uses
- longsword and rapier damage in D&D 5e
- cleric and rogue hit dice
- cure wounds healing
- Damage for many one-handed martial weapons in D&D, from the battleaxe to the warhammer
- Hit dice for several classes when spending them during a short rest
- Random tables with eight entries, such as compass directions or watch results
d8 questions
What shape is a d8?
A regular octahedron, one of the five Platonic solids. Eight equilateral triangles meet four at a time around each of its six corners. Set it on a table and you get a diamond silhouette, which is why it sits so distinctly in a standard seven-dice set.
Why does a d8 roll so far?
Its faces are small and its corners are sharp, so it keeps tipping over instead of settling. The same geometry that makes it fair makes it lively. Most players who lose dice regularly are losing d8s and d20s rather than the flatter, calmer d4 and d6.
Which D&D classes use a d8 hit die?
Clerics, rogues, bards, druids, monks and warlocks all use d8 hit dice in fifth edition. That puts them between the d6 casters and the sturdier d10 and d12 classes. You roll one when you gain a level and when spending hit dice on a short rest.
Can two d8s replace a d16?
Not directly. Adding two d8s gives a curved spread from 2 to 16, not an even one. To get a flat result you would need one d8 for the number and a separate coin flip or odd-even die to decide whether to add eight.