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Poisson Distribution Event Rate Calculator

P(X=k) = λᵏe^(−λ)/k! — events in a fixed interval.

Calculates the Poisson PMF and CDF from event rate λ and number of events k for modelling rare events in a fixed time/space interval.

Priya Venkatesan By Priya Venkatesan
Published Last reviewed 1 min read

Inputs

Results

Enter values and click Calculate to see results.
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How to use this calculator

  1. Fill in the inputs above using the units you already have.
  2. Values update automatically as you type — no submit button needed.
  3. Hover any result row for the underlying formula and intermediate values.

Formula

P(X=k) = e^(−λ) × λ^k / k!

In depth

Calculates the Poisson PMF and CDF from event rate λ and number of events k for modelling rare events in a fixed time/space interval.