Dice Probability Calculator
Get the exact probability distribution for a dice total like 2d6, the chance of hitting a target, the average, and the full range. Computed, not simulated, in your browser.
P(total ≥ target)
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Show the math
The exact distribution is built by convolving each die's uniform 1…S spread, so every possible total and its probability are known precisely, not simulated.
P(total) = (ways to make total) / Sᴺ
Very large dice pools are skipped to keep things instant. All math runs locally in your browser.
What this does
A dice probability calculator gives the exact probability distribution for a dice total like 2d6 — the chance of hitting a target, the average, and the full range.
How to use it
- Enter the number and type of dice.
- Add any modifier.
- Set a target total.
- Read the odds and distribution.
How it works
The full distribution is built by combining every die’s outcomes, so each probability is computed exactly rather than simulated.
Understanding your result
The distribution is exact, computed by counting every combination rather than simulating, so these odds are the true long-run frequencies, not an approximation. The shape is the lesson: summing more dice clusters results toward the middle, so a 7 on 2d6 is far likelier than a 2 or 12. Over a single session, though, real rolls can stray a long way from these averages.
Example
On 2d6 a total of 7 is the most likely, at about 16.7%.
Sources & methodology
Last updated .
Frequently asked questions
Is this simulated or exact?
Exact. The full distribution is built by combining each die’s outcomes, so every probability is precise rather than estimated.
What does P(total ≥ target) mean?
It is the probability the dice total is at least the target value, useful for checks against a difficulty number.
Is my data kept?
No. Everything is computed locally in your browser.
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