Custom Dice Roller

Roll custom dice with any number of sides and any number of dice. Set modifiers for tabletop gaming or probability experiments.

ROLL RESULT
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Individual Rolls
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Raw Sum
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Expected Value
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Notation
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Custom Dice Rolling

A custom dice roller simulates rolling any combination of dice with any number of sides. Standard sets include d4, d6, d8, d10, d12, and d20, but custom rollers extend to any number. This flexibility is essential for tabletop RPGs, board game design, and statistical simulations.

Each roll generates a uniformly random integer between 1 and the number of sides. Multiple dice and modifiers combine to simulate real gaming scenarios. The probability distribution shifts from uniform (single die) to approximately normal (many dice) per the Central Limit Theorem.

Dice Notation

NdS+M: Roll N dice with S sides, add modifier M
NotationMeaningRange
2d6Two six-sided dice2-12
1d20+5One d20 plus 56-25
3d8-2Three d8 minus 21-22

Probability

Expected Value = N × (S + 1) / 2 + M

For a single die, each face has equal probability 1/S. With multiple dice, the sum follows a bell curve centered at the expected value.

Common Uses

  • Tabletop RPGs for attacks, damage, and ability checks
  • Board game prototyping and balance testing
  • Monte Carlo probability simulations
  • Random decision-making tools

Frequently Asked Questions

Are digital rolls truly random?

They use pseudorandom number generators, which are effectively random for gaming. For cryptographic purposes, use a cryptographically secure random source instead.

What is the most common 2d6 result?

7 is most common, achievable with 6 combinations out of 36 (16.7%). Results 2 and 12 are rarest at 2.8% each.

Can I roll odd-sided dice?

Yes. Digital rollers simulate any number of sides perfectly. Physical odd-sided dice are rare but the math works identically.