Dice Probability Calculator
Find the probability of rolling a target sum with any number of dice.
This tool is for informational and educational purposes only. It is not a substitute for professional financial, medical, legal, or engineering advice. See Terms of Service.
Can't find what you need?
Request a ToolHow to Use the Dice Probability Calculator
Enter the number of dice, the number of sides per die, and your target sum. Choose whether you want the probability of rolling exactly that sum, at least that sum, or at most that sum. Results update instantly.
About This Calculator
Dice probability calculations use combinatorics to count the number of ways to achieve a target sum, then divide by the total number of possible outcomes. For n dice with s sides each, there are s^n total equally likely outcomes. This calculator uses dynamic programming to count favorable outcomes efficiently.
Frequently Asked Questions
What is the most common sum for 2d6?
The most common sum when rolling two six-sided dice is 7, with a probability of 6/36 or about 16.67%. There are six combinations that produce 7.
How many outcomes are there for 3d6?
Three six-sided dice have 6^3 = 216 total outcomes. The possible sums range from 3 to 18.
Does this work for non-standard dice?
Yes. You can set any number of sides per die. This works for d4, d8, d10, d12, d20, d100, or any custom die.