How it works
The workflow, examples and limits behind every tool.
Dice totals ↗
Each independent fair die adds its equally likely faces to the current distribution. Sum matching probabilities for the selected comparison.
Example: Two six-sided dice total exactly 7 with probability 6/36 = 16.667%.
1–12 dice, 2–20 sides, fair independent dice only. Numerical probabilities are rounded for display.
Success pool ↗
One die succeeds on faces ≥ threshold. A binomial recurrence combines independent successes.
Example: Three d6, success on 5 or 6, at least one success gives 70.370%.
No exploding dice, rerolls or game-specific rules. Threshold may be sides + 1 to model no possible success.
Take high or low ↗
If single success is p: take-high = 1 − (1−p)²; take-low = p².
Example: On d20, reaching 15 succeeds 30% normally, 51% taking high and 9% taking low.
Two independent fair dice; ignores critical results and modifiers.
Repeated chance ↗
At least one = 1 − (1−p)^attempts. Expected success count = attempts × p.
Example: Three attempts at 50% each give an 87.5% chance of at least one success.
Only independent identical attempts. Not a prediction of an individual outcome.
Local work, explicit limits
Each workspace reports its input and file limits. Imports validate the supported format before asking to replace saved work. Plain text is displayed as text, never executed as markup. Both languages use the same tools; the root address always opens in English, with Chinese under /zh/.