Quick start
- Enter values separated by commas, spaces, or line breaks.
- Choose Sample for a sample data set or Population for the full group.
- Press Calculate standard deviation.
- Review the answer, variance, mean, range, and steps.
Sample vs population
Use Sample when your data is only part of a larger group. Sample standard deviation divides by n - 1, which is the common classroom and survey choice.
Use Population when your list contains every value in the group. Population standard deviation divides by n.
Reading the result
A smaller standard deviation means the values are closer to the mean. A larger standard deviation means the values are more spread out.
The calculator also shows variance because standard deviation is the square root of variance.
Examples from the calculator
Population SD = 2
Sample SD = 2.1380899353
Mean = 19.1666666667
History, privacy, and copying
Recent answers stay visible in the page while you work. The history is kept only in the current browser tab and is not sent to a server.
Copy answer copies the expression and result so you can paste it into notes, homework, a message, or another document.