Question

What Excel formula do I use to calculate the variance between two cells?

Answer 1

You cannot calculate a statistical variance between two cells (values).

Explanation:

Be careful of your definitions. A difference between two values is simply a difference, or subtraction. A "variance" in statistical terms means the collective variation of multiple terms. Variances may be compared with each other for different statistical significance.

HOWEVER, the statistical term 'variance' is NOT the financial or general use one that means a 'difference', and thus it cannot be applied or calculated from only two values.

If you want to calculate the variance of a set of data points in Excel you can use the VAR function (most often) for a sample, or VARP if you are assuming the set includes the full population of values.