A standard dice has six sides. It’s a cube numbered 1 through 6, and it’s the die sitting in almost every board game box you own. Tabletop and role-playing games also use dice with 4, 8, 10, 12, 20, or 100 sides, but when someone just says “a dice,” they mean the six-sided one.
The six-sided die is the default
Six sides, six numbers, one cube. Every face carries a number from 1 to 6, marked with dots rather than digits on most sets. Opposite faces add up to seven, so the 1 sits across from the 6, the 2 across from the 5, and the 3 across from the 4. That arrangement has been standard for roughly two thousand years.
Roll one and any given number comes up 16.67% of the time. Roll two and you get 36 equally likely outcomes, which is where the whole shape of dice probability comes from.
Monopoly, backgammon, craps, Yahtzee. All six-sided.
The other side counts
Role-playing games needed more than six results, so dice makers went looking for other shapes that roll fairly. Five of them were already known to the ancient Greeks as the Platonic solids: shapes where every face is the same regular polygon and the same number of faces meet at every corner. That fairness is the whole point. If the faces are identical, no face is favored.
| Die | Sides | Shape | Common use |
|---|---|---|---|
| d4 | 4 | Tetrahedron | Dagger damage in D&D, small counters |
| d6 | 6 | Cube | Board games, craps, Yahtzee |
| d8 | 8 | Octahedron | Weapon damage, hit dice |
| d10 | 10 | Pentagonal trapezohedron | Percentile rolls, World of Darkness |
| d12 | 12 | Dodecahedron | Barbarian hit dice, big weapons |
| d20 | 20 | Icosahedron | Attack rolls and skill checks in D&D |
| d100 | 100 | Two d10s read together | Percentile tables, loot charts |
The d10 is the odd one out. There’s no Platonic solid with ten faces, because ten identical regular polygons won’t close into a solid. So the d10 uses a pentagonal trapezohedron instead: ten kite-shaped faces in two rings of five, with a sharp point at each end. It was patented as a gaming die in 1906, centuries after the other shapes were already in use.
The d100 is barely a die at all. You roll two d10s, one marked 00 through 90 for tens and one marked 0 through 9 for units, and read them together as a number from 00 to 99, with double zero counting as 100. True hundred-sided balls exist, but they roll forever and nobody enjoys chasing them across the floor.
Which one you actually need
For board games, a pair of d6s covers you.
For D&D or any modern role-playing game, buy the seven-dice set: d4, d6, d8, two d10s, d12, and d20. That’s the full spread, and the d20 does most of the work. Rolling a natural 20 happens 5% of the time, which is exactly why the table cheers when it lands.
Want to try the shapes before buying a bag? You can roll any of them free in your browser, with the rolls happening on your own device. See also what the dots on dice are called and the full breakdown of every die shape.
FAQ
How many numbers are on a dice?
A standard six-sided dice has six numbers: 1, 2, 3, 4, 5, and 6. Each appears once, on its own face. Polyhedral dice carry more, so a d20 shows the numbers 1 through 20 and a d12 shows 1 through 12, always one number per face.
What is a 20-sided dice called?
A d20, or an icosahedron. It’s one of the five Platonic solids, built from twenty identical equilateral triangles. Dungeons and Dragons made it famous: attack rolls, saving throws, and skill checks all run on the d20, with 20 as the best possible result.
Is there a die with 100 sides?
Yes. It’s called a Zocchihedron, invented by Lou Zocchi and released in 1985, and it looks like a golf ball with 100 flattened spots. It rolls for an uncomfortably long time, and published testing found the low and high numbers came up less often than they should.
Why do dice have six sides?
The cube is the simplest shape that’s genuinely fair, easy to carve, and easy to read once it stops. Six identical square faces mean no face is favored. Cubic dice show up in archaeological sites across the ancient world, and the design stuck because nothing improved on it.