Standard Deviation Calculator

How the calculation works

Choose sample or population, then enter your numbers. The variance is the average squared distance from the mean (dividing by n for a population, or n − 1 for a sample). The standard deviation is its square root.

Formula used

σ = √(Σ(x − mean)² ÷ N); s = √(Σ(x − mean)² ÷ (n − 1))

Example

For 10, 12, 23, 23, 16, 23, 21, 16 the mean is 18 and the sample standard deviation is 5.237.