Select from Bernoulli, Binomial, Poisson, Geometric, Negative Binomial, and Discrete Uniform. More about them in here. Discrete Distribution Calculator Select Distribution: Functions of Discrete Random Variables Discrete Uniform Bernoulli Binomial Negative Binomial Geometric Poisson Constant c: Constant d: E(X): V(X): Calculate E(Y): V(Y): a: b: x (for PMF): Calculate PMF: Mean: Variance: p (probability of success): x (0 or 1): Calculate PMF: Mean: Variance: n (number of trials): p (probability of success): x (number of successes): Calculate PMF: Mean: Variance: r (number of successes): p (probability of success): x (number of trials): Calculate PMF: Mean: Variance: p (probability of success): x (number of trials): Calculate PMF: Mean: Variance: λ (mean rate): T (time/space interval): x (number of events): Calculate PMF: Mean: Variance: