# CHIINV

Formulas / CHIINV
Return the appropriate x value based on the accuracy of CHIDIST.
`CHIINV(probability,deg_freedom)`
• probability - required, a probability associated with the chi-squared distribution
• deg_freedom - required, the number of degrees of freedom

## Examples

• `=CHIINV(A2,A3) = 18.306973`

because that is the one-tailed probability of the chi-squared distribution.

• `=CHIINV(A2,A3`

)The example returns #NUM! because a nonnumeric argument causes CHIINV to return the #VALUE! error.

• `=CHIINV(A2,A3)`

This example returns 1 because probability is required to be a number.

## Summary

The CHIINV function is used to calculate the inverse of the CHIDIST function, which calculates the probability that a Chi-Square distributed random variable with df degrees of freedom is greater than or equal to x. CHIINV uses a search process to find the right value of x.

• The CHIINV function is used to find the correct value of x by evaluating the CHIDIST function.
• It is the inverse of the CHIDIST function and returns the corresponding probability of a given value.

What is the CHIINV function?
The CHIINV function is used to return the inverse of the right-tailed probability of the chi-squared distribution. The chi-squared distribution is a type of probability distribution commonly used to analyze sample data. The CHIINV function uses an iterative search technique to return the inverse of the chi-squared distribution.
What happens if the probability is not a number?
The CHIINV function returns an error value if probability is not a number.
What happens if the probability is not between 0 and 1?
The CHIINV function returns the #NUM! error value if the probability is not between 0 and 1.
What happens if the CHIINV function cannot find an x to return in 100 iterations?
The CHIINV function returns the #N/A error value if the CHIINV function cannot find an x to return in 100 iterations. 