z score in Excel

The z-score, also known as a standard score, is used in statistics. It measures the number of standard deviations of a specific number.

To calculate z-score you can use the following formula.

z-score = (x – μ) / σ

x – value

μ – mean

σ – standard deviation

Let’s take a look at the following example. This site iqtestprep.com shows the IQ score of famous people.

I chose just a few examples to illustrate how you can calculate the mean, standard deviation, and z-score.

You can copy the following example.

First NameLast NameIQ
MuhammadAli78
RowanAtkinson178
KobeBryant114
WarrenBuffet145
MileyCyrus120
DavidDuchovny147
ThomasEdison145
JodieFoster132
ArianaGrande105
StephenHawking160
CharlesManson109
OJSimpson89

Calculating standard deviation in Excel

  1. Calculate the mean for the IQ scores, by using the following formula =AVERAGE(C2:C13) and call it mean.
  1. Calculate the standard deviation with this formula: =STDEVPA(C2:C13) and call it stdev.
  2. In cell D2, calculate the z-score for the first IQ: =STANDARDIZE(C2, mean, stdev).
  3. Use autofill to calculate the remaining z-scores.

This is the result of our calculations.

Tomasz Decker is an Excel specialist, skilled in data analysis and financial modeling.