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Geometric Distribution Calculator

A free online tool for calculating probabilities of events following geometric distribution.
The geometric distribution gives the probability that the first occurrence of a success requires x independent trials, each with the success probability p. The probability P that the x-th trial is the first success is described by the formula:
P(X=x) = p(1-p)x-1

x>0, 0<p<1



Probability of success in one trial:p =

Calculate the probability of x trials being required for the first success to occur:
x =
Calculate the total probability of all values x from the interval x1 - x2:
x1 = x2 =

P(X = x):

P(X ≤ x):

P(X ≥ x):