What is CHISQ.INV function in Excel? CHISQ.INV function is one of Statistical functions in Microsoft Excel that returns the inverse of the left-tailed probability of the chi-squared distribution.The chi-squared distribution is commonly used to study variation in the percentage of something across samples, such as the fraction of the day people spend watching television. Syntax of CHISQ.INV function CHISQ.INV(probability,deg_freedom) The CHISQ.INV…