±Free
Binomial probability
Compute exactly k successes and at most k successes in independent trials.
Enter the number of trials n, successes k and per-trial success probability p. The tool evaluates the binomial mass at k and sums masses from zero through k for the cumulative probability.
How to use
- Enter your text, values, or image.
- Adjust the options and run the tool.
- Copy or download your result.
Worked example
Example input
Trials: 3 Successes: 2 Success probability (0–1): 0.5
Example result
{
"exactly": 0.375,
"atMost": 0.875
}Limitations and details
Trials must be independent with the same success probability; n is limited to 10000 and extreme probabilities can underflow.
Inputs and options
- Trials
- Number · Minimum: 0 · Maximum: 10000
- Successes
- Number · Minimum: 0 · Maximum: 10000
- Success probability (0–1)
- Number · Minimum: 0 · Maximum: 1
Frequently asked questions
Is this tool free and private?
Yes. All 300 tools are free in this phase. Processing happens in your browser; your input and files are not sent to our servers.