The number of standard deviations a value is from the mean. z = (x − μ) / σ.

What if standard deviation is zero?

The calculator cannot compute a z-score when std dev is 0 (all values would be the same).

Online Z-Score Calculator

Compute z = (x − mean) / std dev from value, mean, and standard deviation.

Value x

Mean μ

Standard deviation σ

What is a z-score?: The number of standard deviations a value is from the mean. z = (x − μ) / σ.
What if standard deviation is zero?: The calculator cannot compute a z-score when std dev is 0 (all values would be the same).

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