Standard Deviation Calculator

Population and sample standard deviation, variance and mean for any data set.

Frequently asked questions

What is the difference between sample and population SD?

Population standard deviation divides by N and is used when your data is the entire population. Sample standard deviation divides by N-1 (Bessel's correction) and is used when your data is a sample of a larger population. The tool shows both.

How do I enter my data?

Paste numbers separated by spaces, commas or new lines. Decimals and negatives work. The calculator extracts every number automatically.

What else does it show?

The mean, plus both the variance and the standard deviation for sample and population, so you have the full set of dispersion stats.