What is LOGNORM.INV function in Excel? LOGNORM.INV function is one of Statistical functions in Microsoft Excel that returns the inverse of the lognormal cumulative distribution function of x, where ln(x) is normally distributed with parameters Mean and Standard_dev. If p = LOGNORM.DIST(x,…) then LOGNORM.INV(p,…) = x. Use the lognormal distribution to analyze logarithmically transformed data. […]