Dice Roller
Roll any number of dice with any number of sides.
Rolling more dice changes the shape of the outcome
A single twenty-sided die is flat: every result from 1 to 20 is equally likely, so a 20 is exactly as probable as an 11. Roll three six-sided dice instead and the distribution becomes a bell — 10 and 11 each come up about an eighth of the time while 3 and 18 each appear roughly once in 216 rolls. This is why 3d6 and 1d18 are completely different mechanics despite covering similar ranges, and why tabletop systems choose one or the other deliberately.
The practical rule: more dice means results cluster tightly around the average and extremes become rare. Fewer, larger dice means wild swings. Neither is more random — they are differently shaped randomness.
Physical dice are not perfectly fair either
Cheap injection-moulded dice have hollowed pips that shift the centre of mass, rounded corners that vary between faces, and mould-line asymmetries. Measurable bias is common, though usually small enough not to matter in casual play. Casino dice are machined to tight tolerances with flush, density-matched pips precisely because the bias in ordinary dice is real. A digital roll drawn from the browser's cryptographic random source has no such physical asymmetry.
Streaks are what random actually looks like
Rolling four sixes in a row on a d6 happens about once every 1,296 sequences of four — unusual for any given attempt, and completely unremarkable across an evening of play. Human intuition badly underestimates how clustered genuine randomness is, which is why people routinely accuse a fair generator of being broken when it produces a run, and why sequences that "look random" to people are usually too evenly distributed to be genuinely random. Each roll is independent: the dice have no memory of the previous result and no obligation to balance out.
How to use it
- Set the number of dice and the number of sides.
- Roll, and read both the individual dice and the total.
- Remember that more dice narrows the spread around the average.
- Treat streaks as normal — independence means no result is "due".
Before you draw
Is 3d6 the same as 1d18?
No. 1d18 gives every result equal probability, while 3d6 produces a bell curve where 10 and 11 are far more likely than 3 or 18. The ranges overlap but the mechanics behave completely differently.
Are digital dice as fair as physical ones?
Usually fairer. This roller draws from the browser's cryptographic random source and has no physical asymmetry, whereas ordinary moulded dice have measurable bias from hollowed pips and uneven corners.
I rolled the same number five times — is it broken?
Almost certainly not. Streaks are a normal feature of independent random draws, and people consistently underestimate how often they occur. A sequence with no runs at all would be the suspicious result.
Does the previous roll affect the next one?
No. Each roll is independent, and no outcome becomes more likely because it has not appeared recently. Believing otherwise is the gambler's fallacy.
Disclaimer: These tools are for games, classrooms, and informal group decisions. They are not audited for regulated lotteries, gambling, or any draw with legal requirements, and should not be used to make financial, medical, legal, or safety decisions.