Free Online Poisson Distribution Calculator, Enter Value of Poisson random variable (x) & Average rate of success (μ), then hit on "Calculate" button and get result.

Calculation results

Poisson Distribution Calculator

Poisson Distribution Formula

Probability of exactly x successes (P(X=x)) = (e^{-μ} * μ^{x}) / x!

Probability of less than x successes (P(X

Probability of less than or equal to x successes (P(X≤x)) = Σ (P(X=k)) for k = 0 to x

Probability of more than x successes (P(X>x)) = 1 - P(X≤x)

Probability of greater than or equal to x successes (P(X≥x)) = 1 - P(X