Free Binomial Distribution Probability Calculator (P(X = k), P(X ≤ k)) Online
Calculate exact binomial probability P(X = k), cumulative probability P(X ≤ k), expected mean μ = np, and variance for n independent trials. — 100% free online utility, zero sign-up, zero paywalls, and private client-side processing.
How It Works
Enter Number of Trials (n)
Input total trials count.
Enter Success Probability (p)
Input chance of success on a single trial (0 to 1).
Enter Successes (k)
Input target success count.
Review Probability Table
View exact P(X = k), cumulative P(X ≤ k), and P(X ≥ k).
Frequently Asked Questions
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