What does a z-score of 2 mean?

It means the value is 2 standard deviations above the mean, which in a normal distribution puts it in roughly the top 2.3% of values.

Z-Score Calculator

A z-score tells you how many standard deviations a value is from the mean of its distribution.

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Formula

z = (x − μ) / σ

How Standard Deviation Measures Spread, Explained

The standard deviation formula worked through step by step, showing exactly what each part of the calculation represents.

Standard Deviation Calculator

Calculate the population standard deviation of up to 5 numbers.

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Calculate the average of up to 10 numbers.

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