How to Calculate Z-Scores with STANDARDIZE

STANDARDIZE turns a value into a z-score — how many standard deviations from the mean — so you can compare different scales.

You will learn to

• Calculate a z-score with STANDARDIZE
• Interpret a z-score where lower is better
• Combine z-scores from two different scales

How it works

A z-score tells you how many standard deviations a value sits above (positive) or below (negative) the mean. =STANDARDIZE(x, mean, standard_dev) calculates (x − mean) ÷ standard_dev; you supply the mean and standard deviation, usually with AVERAGE and STDEV.S.

Z-scores put different measures on the same scale. Push-ups are counted and run times are in minutes, but a z-score of +1.2 on one and −1.2 on the other are equally impressive (for time, negative is good). Add or subtract z-scores to build fair combined indexes.

=STANDARDIZE(B4,AVERAGE(B2:B11),STDEV.S(B2:B11))