Loading tool...
About This Tool
The Standard Deviation Calculator computes both population and sample standard deviation from a list of numbers. It also shows variance, mean, sum of squares, and count — everything you need for basic statistical analysis.
Standard deviation measures the spread or dispersion of a data set relative to its mean. A low standard deviation indicates data points are close to the mean, while a high value indicates greater spread. It is the most widely used measure of variability in statistics.
Enter your data points separated by commas, spaces, or new lines. The tool computes both σ (population SD, dividing by N) and s (sample SD, dividing by N−1) so you can use whichever is appropriate for your analysis.