# The Excel CHISQ.INV Function

Related Functions:
CHISQ.DIST
CHISQ.INV.RT

## Function Description

The Excel Chisq.Inv function calculates the inverse of the left-tailed probability of the Chi-Square Distribution.

The function is new in Excel 2010 and so is not available in earlier versions of Excel.

The syntax of the function is:

CHISQ.INV( probability, degrees_freedom )

Where the function arguments are:

 probability - The probability of the left-tailed chi-square distribution, for which you want to find the value of x. degrees_freedom - The number of degrees of freedom (must be an integer between 1 and 1010).(If the supplied value is a decimal, this is truncated to an integer).

## Chisq.Inv Function Examples

The Excel Chisq.Inv function is used in the spreadsheet below, to calculate the inverse of the left-tailed chi-square distribution for five sets of values.

Formulas:
A
1=CHISQ.INV( 0.5, 1 )
2=CHISQ.INV( 0.75, 1 )
3=CHISQ.INV( 0.1, 2 )
4=CHISQ.INV( 0.8, 2 )
5=CHISQ.INV( 0.25, 3 )
Results:
A
10.454936423
21.323303697
30.210721031
43.218875825
51.212532903

For further details and examples of the Excel Chisq.Inv function, see the Microsoft Office website.

## Chisq.Inv Function Errors

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

Common Errors
 #NUM! - Occurs if either:The supplied probability value is < 0 or ≥ 1;The supplied degrees_freedom argument is <1 or >1010. #VALUE! - Occurs if any of the supplied arguments is non-numeric.