The *sum of squares*, or sum of squared deviation scores, is a key measure of the variability of a set of data. The mean of the sum of squares (*SS*) is the *variance* of a set of scores, and the square root of the variance is its *standard deviation*.

This simple calculator uses the computational formula *SS* = Σ*X*^{2} - ((Σ*X*)^{2} / *N*) - to calculate the sum of squares for a single set of scores.

Just add your scores into the text box below, either one score per line or as a comma delimited list, and hit Calculate.

No calculation performed yet!