Random Dice Roll Generator (D12)
About the D12
The twelve-sided die (D12) is shaped as a regular dodecahedron — one of the five Platonic solids, with each face being a regular pentagon. It produces numbers from 1 to 12 with equal probability. In D&D, the D12 is the hit die for Barbarians and the damage die for greataxes.
This digital version uses the Web Crypto API to produce cryptographically secure random numbers, ensuring a perfectly uniform distribution with no physical bias.
Probability
The expected value of a single D12 roll is 6.5. Each of the twelve faces has an exactly equal 8.33% probability of landing face up.
Use cases
- D&D Barbarian hit dice and greataxe damage
- Random month selection (1–12 maps to Jan–Dec)
- Random hour on a clock face
- Board games that use 12-sided dice
- Astrology — random zodiac sign selection
How it works
- Your browser generates a cryptographically secure 32-bit unsigned integer
- The integer is mapped to the range 1–12 using modular arithmetic
- The result is displayed instantly — no server request needed
- Roll history and stats are tracked locally in your browser session
Privacy and security
Your dice rolls never leave your device. This tool runs entirely in your browser using client-side JavaScript — no API calls, no server logs, no cookies, and no tracking of generated values.