🎲 Dice Roller & Coin Flip
Choose your dice and how many, then roll, or flip a coin. Uses cryptographic randomness for a fair result.
Rolls virtual dice (d4 to d100) or flips a coin using your browser\'s cryptographic random generator, so every result is fair and unpredictable, good for tabletop and board games, D&D, or any decision. Roll up to 100 dice at once and it totals them. 🔒 In your browser.
How the dice roller & coin flip works
Pick a die type (from a four-sided d4 up to a hundred-sided d100) and how many to roll, then hit Roll. Each die is generated with your browser's cryptographic random-number generator (Web Crypto), which is unbiased and unpredictable, unlike simple pseudo-random shortcuts. To turn raw random bytes into a fair 1-to-N result the tool uses rejection sampling: values that would fall outside a whole multiple of N are discarded and re-drawn, which avoids the slight bias toward low numbers that a plain remainder (modulo) would introduce. When you roll several dice, the tool shows each result and the total. The coin flip returns heads or tails the same fair way.
Everything runs locally, so there's no server round-trip and the rolls can't be tampered with. Roll up to 100 dice at once for big damage rolls or statistics. For polyhedral RPG dice (d4/d6/d8/d10/d12/d20), pick the matching option; d100 covers percentile rolls.
Frequently asked questions
How does an online dice roller work?
It generates a random number from 1 to the number of sides for each die, using the browser's cryptographic random generator so the result is fair and unpredictable. This tool shows each die and totals them.
Are the dice rolls really random?
Yes. They use the Web Crypto API's cryptographically secure random generator, which is unbiased and can't be predicted, rather than a simple pseudo-random function. Every face has an equal chance.
What dice can I roll?
The standard polyhedral set, d4, d6, d8, d10, d12, d20, plus d100 for percentile rolls, and a coin flip. Roll from 1 up to 100 dice at once.
Can I roll multiple dice at once?
Yes, set the count and the tool rolls them together, showing each result and the sum. Handy for damage rolls, stat generation or any multi-dice throw.
Do I need dice or an app?
No. This works in any browser, even offline once loaded, so it's a quick stand-in when you've lost your dice or need more than you have on hand.
What does "3d6" mean and how do I roll it?
It is dice notation for rolling three six-sided dice and adding them, common for tabletop games. Choose the d6, set the count to 3, and the tool rolls all three and shows the total. The general form NdX means "roll N dice of X sides".
Why can rolling many dice give a total near the middle more often?
Each die is uniform, but their sum is not: adding several dice makes middle totals far more likely than the extremes, because there are more combinations that produce them. Three d6 total 10 or 11 much more often than 3 or 18, that bell-shaped spread is a property of summing dice, not a flaw in the randomness.
Is a coin flip really 50/50 here?
Yes, heads and tails are drawn from the same unbiased cryptographic source with exactly equal probability, so it is a fair 50/50 with no hidden weighting.