OhMyCalc

Binomial Distribution Calculator

Calculate the probability of exactly k successes in n independent Bernoulli trials with success probability p.

How to Use the Binomial Distribution Calculator

  1. Enter the number of trials n, successes k, and probability p.
  2. Click Calculate to find P(X = k).
  3. The mean and standard deviation of the distribution are also shown.

Schnellreferenz

VonNach
n=10, k=5, p=0.5P ≈ 0.2461
n=20, k=0, p=0.1P ≈ 0.1216
n=6, k=6, p=0.5P ≈ 0.0156
n=100, k=50, p=0.5P ≈ 0.0796
Mean = npExpected successes

Anwendungsfälle

Formel

P(X=k) = C(n,k) × p^k × (1−p)^(n−k). Mean = np. Std dev = √(np(1−p)).

Häufig gestellte Fragen

What is the binomial distribution?
The probability distribution for the number of successes in a fixed number of independent trials, each with the same success probability.
What is C(n,k)?
The binomial coefficient 'n choose k' = n! / (k!(n−k)!), the number of ways to choose k items from n.
When is it used?
For coin flips, defect counts, survey yes/no responses, and any fixed-trial success/failure experiment.