Author: Oscar Cronquist Article last updated on May 11, 2022

The EXPON.DIST function calculates the exponential distribution representing an outcome in the form of probability.

This function was introduced in Excel 2010, it has replaced the EXPONDIST function which is now outdated.

Formula in cell E3:


Excel Function Syntax



x Required. The value of the function.
lambda Required. The parameter value.
cumulative Required. A boolean value.
TRUE - cumulative distribution function.
FALSE - probability density function.


The EXPON.DIST function returns

  • #VALUE! error value if lambda or x is non-numeric.
  • #NUM! error value if:
    • x < 0 (zero)
    • lambda <= 0 (zero)

The general equation to calculate the cumulative distribution function:

The general equation to calculate the probability density distribution:

Link to Wikipedia: Exponential distribution