The d8, properly introduced
Eight-sided dice are ancient too: octahedral examples survive from Ptolemaic Egypt and Rome, some inscribed with letters for divination rather than numbers for play. The modern d8 arrived in game shops with the first Dungeons & Dragons boxed sets in the mid-1970s, sold as part of the now-standard polyhedral family.
Roll it for: weapon damage in tabletop rpgs; eight-way random choices; teaching probability with a non-cube die. And if the d8 isn't the die your game asks for, the full dice roller has the other five.
Every throw comes from your browser's cryptographic generator through rejection sampling, which is why each of the 8 faces lands at exactly 12.5% rather than approximately. How random is random covers why the daily numbers elsewhere on this site are deliberately drawn the opposite way.
- 8, numbered 1 to 8
- Octahedron, a Platonic solid
- 12.5% — exactly 1 in 8
- 4.5
- averages 9; totals range 2 to 16
- two 8s in a row: 1 in 64
D8 — frequently asked
A 8-sided die shaped as a octahedron, one of the five Platonic solids. Two pyramids glued base to base. Faces are numbered 1 to 8, and on a fair d8 each lands with exactly a 12.5% chance.
One in 8, or 12.5%, the same as every other face. Rolling two 8s back to back happens once in 64 attempts. The roller here uses rejection sampling on a cryptographic generator, so those odds hold exactly.
4.5. A fair die averages the midpoint of its range, so 2×d8 averages 9 and 3×d8 averages 13.5. Single rolls are flat: an average result is no more likely than a 8 or a 1.
Weapon damage in tabletop RPGs; Eight-way random choices; Teaching probability with a non-cube die. Beyond those, any decision with 8 options maps onto it directly.