Coin Flip & Dice Roller
Flip a coin or roll any number of dice, instantly, with unbiased randomness.
Coin Flip
Dice Roller
How to use this tool
Click "Flip Coin" for heads or tails. For dice, choose how many dice and which die type, then click "Roll Dice".
About this tool
Uses crypto.getRandomValues() with rejection sampling, so every coin side and every die face has an exactly equal chance of being chosen — unlike a naive Math.random() approach, which can be subtly biased.
100% client-side. No data is uploaded, logged, or stored.
Frequently asked questions
Is the randomness fair?
Yes. Coin flips and dice rolls use crypto.getRandomValues() with rejection sampling, so every outcome has exactly equal probability, with no bias toward any side or number.
How many dice can I roll at once?
Up to 20 dice per roll, with any of the standard tabletop die sizes: d4, d6, d8, d10, d12, d20, or d100.