Calculate standard deviation and variance from a list of numbers, with sample versus population made explicit instead of guessed.
Sample or population - which should I choose?
Choose sample when your list is only a sample from a larger group and you want to estimate the larger group's spread. Choose population when your list already is the full group you care about. This is the n - 1 versus n choice.
Why is my result different from another calculator?
Most often because the other page silently chose sample or population. This page prints which one it used. If the convention matches and the list matches, the arithmetic should match too.
Can standard deviation be zero?
Yes. If every value is the same, every distance from the mean is zero, so both the variance and the standard deviation are zero.
What does a large standard deviation mean?
It means the numbers are more spread out from the mean. The unit stays the same as the data itself, which makes it easier to read than variance, whose unit is squared.
How should I enter my list?
Separate values with commas, spaces, semicolons, or new lines. Do not use commas inside a number, because a comma always splits the list on this page.