z
Z-Score Calculator
How many standard deviations a value sits above or below the mean, and the share of a normal distribution below it.
Result…
How it's calculated
z = (x − μ) ÷ σ share below = Φ(z)
A z-score puts values from different scales on one ruler: z = 1.5 means one and a half standard deviations above the mean. The percentages come from the standard normal distribution, so they hold only when the data is roughly bell-shaped.
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