Standard Deviation Calculator

Calculate mean, variance, and standard deviation from any list of numbers.

Data (comma or space separated)

Type

Count (n)

Mean (x̄)

5.5000

Variance (σ²)

3.5000

Std deviation (σ)

1.8708

How it works

Sample SD: divide sum of squared deviations by (n − 1).

Population SD: divide by n. Use sample when data is a subset of a larger group.

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