Poisson Probability: λ = 5, k = 3 Events
With an average rate of 5 events per interval, the probability of observing exactly 3 events is approximately 14.04%.
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.
Calculate the Poisson probability of exactly 3 events occurring when the average rate is 5 events per interval.
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.