What a z-score tells you.
A z-score is how many standard deviations a value is from the mean; with a normal distribution, it also gives the share of values below it.
By Suraj Kumar2 min read
A z-score puts values from different scales on one.
The sum.
(Value − mean) ÷ standard deviation: 85 on a test with a mean of 70 and a standard deviation of 10 is 1.5.
Comparing.
Two results on different tests can be compared by their z-scores.
Further reading
Topics: z score calculator · how to calculate z score · z score formula · standard score · z score percentile
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