Dice Success Probability (per-die condition)
Supports d4/d6/d8/d10/d12/d20, advantage/disadvantage, exploding on max, and P(X ≥ N).
Die type
d4
d6
d8
d10
d12
d20
Choose the die.
Number of dice
1–50 via slider (you can type up to 200).
Target number
If exploding is ON, you can set a target above the die’s max.
Condition
Less than ( < )
Equal to or less ( ≤ )
Equal to ( = )
Equal to or greater ( ≥ )
Greater than ( > )
Roll mode
Normal (1 die)
Advantage (keep higher of 2)
Disadvantage (keep lower of 2)
Disabled when exploding is ON.
Exploding on max (adds & rerolls)
Exact equals to multiples of the max are impossible under always-exploding.
At least N successes
Shows P(X ≥ N) across the dice.
Single-die success (p)
—
Expected successes
—
P(≥ 1 success)
—
P(≥ 1 success)
—
Distribution: successes out of
—
dice
Binomial(n, p). Roll mode applies per-die; exploding modifies the single-die p.
Exact and cumulative probabilities
k successes
C(n,k)
P(X = k)
P(X ≥ k)