Roll any dice, get honest odds.
Pick how many dice, choose the sides from d4 to d100 or a custom die, and add an optional modifier. Every die is rolled with equal odds, so your total is fair for RPGs, board games and quick decisions.
Your dice
What this means
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How dice rolling works
Types of Dice
Standard dice (d6) have 6 sides numbered 1-6. Polyhedral dice used in tabletop RPGs include d4 (tetrahedron), d8 (octahedron), d10 (pentagonal trapezohedron), d12 (dodecahedron), d20 (icosahedron), and d100 (percentile).
Dice Probability Basics
Each face on a fair die has an equal probability. For a d6, each face has a 1/6 (16.7%) chance. When rolling multiple dice, the probability distribution forms a bell curve centered on the average roll. Two d6 most commonly sum to 7.
Dice in Tabletop Gaming
Tabletop RPGs like Dungeons and Dragons use notation like 2d6+3 (roll two six-sided dice and add 3). Different dice serve different purposes: d20 for attack rolls and skill checks, d6 and d8 for damage, d100 for percentile rolls.
Expected Values and Statistics
The expected (average) value of a single die is (sides + 1) / 2. For a d6, the average is 3.5. For multiple dice, multiply by the number of dice. The minimum roll is the number of dice, and the maximum is dice times sides.
Common questions
Are virtual dice truly random?
This roller uses Math.random(), which provides pseudo-random numbers sufficient for gaming purposes. For cryptographic randomness or gambling, hardware random number generators are used. For tabletop gaming, pseudo-random is perfectly adequate.
What is the most likely result when rolling 2d6?
The most likely sum is 7, with a probability of 6/36 (16.7%). There are six ways to make 7 (1+6, 2+5, 3+4, 4+3, 5+2, 6+1) compared to only one way each for 2 (1+1) and 12 (6+6).
What does 2d6 notation mean?
The notation NdS means roll N dice with S sides each. 2d6 means two six-sided dice. 1d20 means one twenty-sided die. 4d6 means four six-sided dice. Some notations add modifiers like 2d6+3.
What is the average roll for common dice?
Average rolls: d4=2.5, d6=3.5, d8=4.5, d10=5.5, d12=6.5, d20=10.5, d100=50.5. For multiple dice, multiply by the number of dice. Two d6 have an average of 7.
How many dice can I roll at once?
This calculator supports rolling up to 100 dice at once. Each die is rolled independently, and the individual results, sum, and average are all displayed. The chart shows the distribution of individual roll values.
These are pseudo-random rolls from Math.random(), fair for tabletop games and casual draws but not for gambling or cryptographic use.