Dice Roller and Coin Flip roll
Roll dice of any common size or flip coins, with a running distribution of results.
What this tool does
Dice and coins are the oldest randomisers there are, useful when a physical die is missing from a board game, when deciding an order, or when demonstrating probability.
This tool supports four, six, ten, and twenty sided dice and rolls several at once. Alongside the individual results it reports the total, the highest and lowest values, and the average, which covers rules that sum multiple dice.
A running distribution updates with every roll, showing how many times each face appeared and its share of the total. Roll enough times and you can watch the proportions converge toward the theoretical value, which makes the tool useful for teaching probability. Randomness comes from the browser cryptographic generator with modulo bias removed.
When to use it
Use it as a substitute for physical dice in board games and tabletop roleplaying, to decide an order among several people, to make a quick arbitrary decision, or to demonstrate how distribution changes with the number of trials.
Input and output examples
Two six-sided dice
Rolls 4 and 5 / total 9 / average 4.50
Matches board game rules that sum two dice.
Ten coin flips
Six heads, four tails
Skew in a small sample is expected.
Notes and limitations
The running distribution is lost when you leave the page and resets when the mode or die size changes. Clusters in a small number of rolls are entirely normal: equal probability means proportions converge over many trials, not that every outcome appears evenly. Rolling a six four times out of ten is unremarkable.
Frequently asked questions
My results look skewed.
That is normal with few trials. Keep rolling and the running distribution moves toward the theoretical values.
Is the history saved?
No. It resets when you reload the page or change the settings.