Binomial Probability Calculator
Calculate the probability of exactly k successes in n independent trials.
- Free Online Tool
- Instant Results
- Mobile Friendly
- No Installation
- Secure & Private
Understanding This Calculator
Binomial Formula
Probability of exactly k successes in n trials.
P(X=k) = nCk × p^k × (1-p)^(n-k)
- n: Total trials
- k: Number of successes
- p: Probability of success per trial
Example 1
Flip a coin 5 times (n=5). Probability of exactly 3 heads (k=3, p=0.5).
- 5C3 = 10
- 0.5³ × 0.5² = 0.03125
- P = 10 × 0.03125 = 0.3125 (31.25%)
How to Use
- Enter number of trials.
- Enter number of successes.
- Enter probability of success (as decimal, e.g., 0.5).
Frequently Asked Questions
How do I use the Binomial Probability Calculator?
Enter your values in the input fields, and the result will appear instantly.
Is this calculator free to use?
Yes, this calculator is 100% free and does not require any registration or subscription.
Is it mobile-friendly?
Absolutely! Our tool is optimized for all devices, including mobile phones, tablets, and desktop computers.