The Excel CHIDIST Function

Related Function:
CHIINV Function

In Excel 2010, the Chidist function has been renamed the Chisq.Dist.Rt function.

Although it has been replaced, the Chidist function is still available in Excel 2010 (stored in the list of compatibility functions), to allow compatibility with earlier versions of Excel.

Basic Description

The Excel Chidist function calculates the right-tailed probability of the chi-square distribution.

The syntax of the function is:

CHIDIST( x, degrees_freedom )

Where the function arguments are:

x-The value at which the chi-square distribution is to be evaluated (must be ≥ 0).

The number of degrees of freedom (must be an integer between 1 and 1010).

(If the supplied degrees_freedom is a decimal, this is truncated to an integer).

Chidist Function Examples

Chi-Square Right-Tailed Distribution with 1, 2 and 3 Degrees of Freedom
  Right-tailed chi-square dist. with 1, 2 & 3 degrees of freedom

The above chart on the right shows the right-tailed chi-square distribution, with 1, 2 and 3 degrees of freedom.

The value of any of these functions, at a specified value of x can be calculated using the Excel Chidist function. Examples are shown in the spreadsheet below:

1=CHIDIST( 0.5, 1 )
2=CHIDIST( 2.5, 1 )
3=CHIDIST( 0.5, 2 )
4=CHIDIST( 0.5, 3 )
5=CHIDIST( 8, 3 )

Further information and examples of the Excel Chidist function are provided on the Microsoft Office website.

Chidist Function Errors

If you get an error from the Excel Chidist function this is likely to be one of the following:

Common Errors

Occurs if either:

  • The supplied value of x is negative
  • The supplied degrees_freedom argument is <1 or >1010.
#VALUE!-Occurs if any of the supplied arguments are non-numeric.