Dice Roller
Roll one or more dice of any type — d4, d6, d8, d10, d12, d20 — and see results with sum and statistics.
Outcome Distribution
How It Works
The Dice Roller simulates rolling standard polyhedral dice — d4, d6, d8, d10, d12, d20, and d100 — using cryptographically secure randomness from your browser’s crypto.getRandomValues. Pick the die type and how many to roll at once (from 1 to a few hundred), click Roll, and every individual result is shown alongside the running total and average. The tool uses rejection sampling so the distribution is exactly uniform — for example, a d6 produces each face with probability exactly 1/6, with no modulo bias from dividing a power-of-two random source by a non-power-of-two die size (the trap that off-the-shelf code often falls into). The d100 (percentile) is treated as a single 1–100 roll, not two d10s, so the distribution is genuinely uniform across all 100 outcomes. Use cases include tabletop role-playing games when physical dice are unavailable, generating uniform random numbers within standard ranges, demonstrating the law of large numbers (rolling 1,000 d20s and seeing the average converge near 10.5), and settling group decisions fairly.
Use Cases
- Rolling dice for tabletop role-playing games when physical dice are unavailable
- Generating random numbers within non-standard ranges
- Teaching probability distributions by rolling many dice
- Settling disputes or making random decisions in a group
Frequently Asked Questions
- Is the distribution exactly uniform?
- Yes. The tool uses rejection sampling on the underlying random bytes, so a d6 gives each face exactly 1/6 probability — no modulo bias.
- What is a d100 roll exactly?
- A single uniform integer from 1 to 100. Some tabletop conventions roll two d10s (tens and units); this tool produces the same distribution either way, but as a single number.
- Can I roll 100 dice at once?
- Yes. The tool handles up to several hundred per click, and shows individual results, the total, and the average.
- Why is the average not exactly the expected value?
- With small sample sizes you see natural variance. Roll 1,000 d20s and the average will sit very close to 10.5 (the expected value).
- Are my rolls sent anywhere?
- No. They are generated in your browser and exist only in the current page.