D8 Roller
A D8 is an eight-sided polyhedral die shaped like an octahedron, yielding outcomes from 1 to 8 with a 12.5% chance per face.
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0Exact Mathematical Probability
Combinatorial EngineCalculates discrete binomial distributions, probability density, and cumulative odds for the active dice expression.
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| Total | Ways | Exact % | ≥ At Least | ≤ At Most |
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Roll N Times (Multi-Trial Simulation)
Execute up to 10,000 repeated trials to calculate empirical distributions and statistics.
Empirical Frequency Table
| Roll Total | Hits (Count) | Frequency Bar | Percentage |
|---|---|---|---|
| Click "Run Trials" to simulate rolls and generate frequency data. | |||
About the D8 (Regular Octahedron)
The D8 is a staple polyhedral die popular in fantasy roleplaying games for medium martial weaponry such as longswords, rapiers, and battleaxes, as well as clerical cure wounds spells and bardic inspiration dice.
Geometric Properties
Regular octahedron with 8 equilateral triangular faces, 6 vertices, and 12 edges. Structurally, it resembles two square pyramids fused at their bases.
Common Tabletop & Gaming Uses
- • One-handed martial weapon damage: Longsword, Rapier, Morningstar
- • Hit dice for Clerics, Druids, Monks, Rogues, Warlocks, and Bards
- • Healing spells like Cure Wounds (1d8 + modifier)
- • Directional determination on an 8-point compass rose (N, NE, E, SE, S, SW, W, NW)
D8 Probability Basics
Each face from 1 to 8 has an equal 12.50% probability on a fair single D8 roll.
| Face Value | Theoretical Odds | Exact Percentage |
|---|---|---|
| 1 | 1/8 | 12.50% |
| 2 | 1/8 | 12.50% |
| 3 | 1/8 | 12.50% |
| 4 | 1/8 | 12.50% |
| 5 | 1/8 | 12.50% |
| 6 | 1/8 | 12.50% |
| 7 | 1/8 | 12.50% |
| 8 | 1/8 | 12.50% |