Why does rolling a 7 with two six-sided dice happen almost six times as often as rolling a 2 or a 12? The math behind it is straightforward once you see every possible combination laid out — and this tool computes that exact breakdown for any number of dice and any number of sides.
What Is the Dice Probability Calculator?
Choose how many dice you’re rolling and how many sides each die has, and the tool computes the full probability distribution across every possible sum using exact combinatorial convolution — not a random simulation — then shows you the odds for any specific target sum.
How to Use It
- Open the tool at /tools/dice-probability-calculator.
- Set the number of dice and the number of sides per die.
- Optionally enter a target sum to see its exact probability.
- Review the full probability table across every possible outcome.
- Use the results to evaluate board game mechanics, tabletop RPG rolls, or general probability questions.
Key Features
- Exact combinatorial math, not Monte Carlo approximation — every percentage is mathematically precise.
- Supports up to 10 dice and 100 sides per die.
- Full distribution table showing the probability of every achievable sum at once.
- Verified against the standard 2d6 textbook distribution (7 = 16.67%, matching 6/36 exactly).
When to Use This Tool
- Designing or balancing tabletop game mechanics that rely on dice sums.
- Checking the odds of a specific roll in Yahtzee, Catan, D&D, or similar games.
- Teaching or learning basic probability and combinatorics with a concrete, visual example.
Try It Now
Open Dice Probability Calculator directly, or press ⌘K and type the tool name from anywhere on the site.
Part of the Math & Numbers collection on WebdevToolbox — free, browser-based developer tools with no login required.