Math · Statistics

Standard Deviation Calculator

Compute both population and sample standard deviation with variance, mean and a full step-by-step deviation table.

Standard deviation
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Sample: s = √( Σ(x₀ − x̄)² / (n − 1) )     Population: σ = √( Σ(x₀ − μ)² / n )
Variance is the square of the standard deviation; the mean is subtracted from each value before squaring.

Sample & population

Both formulas shown, with the correct divisor.

Deviation table

Each value's deviation and squared deviation listed.

Variance included

Variance, mean, sum and count all displayed.

Instant results

Every keystroke recalculates the whole table.

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