Dice Roll Sum Probability Calculator
Local ProcessingCalculate the probability of rolling an exact target sum with multiple s-sided dice.
How It Works & Processing Standards
Enter values above to calculate results automatically. Check each input field for guidance and units.
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Counts every outcome to find the chance the dice add up to exactly your target. Works for d20 and other dice, not just d6.
How to Use Dice Roll Sum Probability Calculator
- 1Number of diceFrom 1 to 20.
- 2Sides and targetSides per die (usually 6) and the sum you want.
- 3Read the probabilityShown as a percentage.
Examples
Two dice, sum 7
Input: 2 dice, 6 sides, sum 7
Result: 16.6666666667%
Three dice, sum 10
Input: 3 dice, 6 sides, sum 10
Result: 12.5%
Common Use Cases
- The chance of the sum you need in a board game
- Setting difficulty checks in a tabletop RPG
- Checking probability class examples
Frequently Asked Questions (FAQ)
Why is 7 the most likely sum with two dice?
Six combinations make 7 — (1,6), (2,5) … (6,1) — out of 36, which is 1/6.
What about "10 or more"?
This gives exactly the target sum. Add the probabilities of each sum for "or more".