How to calculate a z-score in Excel

Q: Is there a built-in function?

Yes, STANDARDIZE: =STANDARDIZE(B2,AVERAGE($B$2:$B$9),STDEV.S($B$2:$B$9)) gives the same result.

Q: How do I turn a z-score into a percentile?

Use =NORM.S.DIST(C2,TRUE), the share of a normal distribution below that z-score.

Formula (Excel and Google Sheets)

=(B2-AVERAGE($B$2:$B$9))/STDEV.S($B$2:$B$9)

Subtract the mean and divide by the standard deviation: =(B2-AVERAGE($B$2:$B$9))/STDEV.S($B$2:$B$9).

Result on the example: one result per row in C2, filled down to C9
Works in: Excel 2010 and later
Google Sheets: Same formula

See it work

The formula is already in C2, filled down to C9. Change any input and the result updates, or edit the formula to experiment.

How it works

The mean is 75.75 and the standard deviation about 9.82. Student D's 90 is 14.25 above the mean, which is 1.45 standard deviations, so the z-score is 1.45. Negative z-scores are below the mean. The $ signs keep every row comparing against the same mean and spread.

=(B2-AVERAGE($B$2:$B$9))/STDEV.S($B$2:$B$9)

Result-0.7889292278

B268
The value in B2.
$B$2:$B$98 rows × 1 col: 68, 74, 81, 90, …
A range: 8 cells in one column.
AVERAGE($B$2:$B$9)75.75
AVERAGE: Arithmetic mean of the numbers.
- number1$B$2:$B$98 rows × 1 col: 68, 74, 81, 90, …
B2-AVERAGE($B$2:$B$9)-7.75
The - operator subtracts.
STDEV.S($B$2:$B$9)9.823441352
STDEV: Sample standard deviation (same as STDEV.S).
- number1$B$2:$B$98 rows × 1 col: 68, 74, 81, 90, …
B2-AVERAGE($B$2:$B$9))/STDEV.S($B$2:$B$9)-0.7889292278
The / operator divides.

In Google Sheets

The same formula works in Google Sheets: =(B2-AVERAGE($B$2:$B$9))/STDEV.S($B$2:$B$9). We ran it in Google Sheets mode on the same data and it returns the same results.

Other ways to do it

Each one was run on the same example sheet.

Formula	Result	When to use it
=(B2-AVERAGE($B$2:$B$9))/STDEV.P($B$2:$B$9)	-0.84, -0.19, 0.57…Different result	Use the population standard deviation when the list is the whole group. Slightly larger z-scores, because STDEV.P is smaller.

Common mistakes

Without $, the mean and standard deviation ranges shift as you fill down and each row compares against a different group.
Calculating AVERAGE and STDEV.S in every row is fine for small lists; for large ones, put them in two cells and refer to those.

Try it yourself

Same data, empty answer cell. Your formula is graded instantly, then re-checked on changed data, so a typed-in number won't pass.

Calculate a z-score

In C2, calculate the z-score of the exam score (how many standard deviations it is from the mean), then fill down to C9.

Questions

Is there a built-in function?

Yes, STANDARDIZE: =STANDARDIZE(B2,AVERAGE($B$2:$B$9),STDEV.S($B$2:$B$9)) gives the same result.

How do I turn a z-score into a percentile?

Use =NORM.S.DIST(C2,TRUE), the share of a normal distribution below that z-score.

Checked by running on 2026-10-30: every formula and result on this page was calculated by the Spreadsheet Practice formula engine, in both Excel and Google Sheets modes.