Poisson Probability: λ = 10, k = 10 Events
With an average rate of 10 events, the probability of observing exactly 10 is approximately 12.51%.
How to use this tool
- Enter rate (λ) and events (k) in the fields above.
- Results update instantly as you type — or click Calculate.
- Read your p(x = k) and the full breakdown beneath it.
Use the Poisson distribution to find the probability of observing exactly the expected number of events (k = λ = 10).
Frequently asked questions
- When should I use the Poisson distribution?
- Use Poisson when counting events in a fixed interval of time or space, where events occur independently at a known average rate λ. Examples: emails per hour, accidents per week, typos per page.