Standard Deviation Calculator
Enter a set of numbers to calculate standard deviation, variance, mean, range and count. Choose whether your data represents a population or a sample.
How to Use the Standard Deviation Calculator
Enter a set of numerical values to calculate the mean, variance and standard deviation for the selected data type.
Practical Example
For the values 2, 4, 4, 4, 5, 5, 7 and 9, the population mean is 5 and the population standard deviation is 2.
Factors That Affect the Result
The result depends on the values entered and whether you use the population or sample formula. Outliers and data spread can strongly affect standard deviation.
Frequently Asked Questions
What does a higher standard deviation mean?
It generally indicates that values are more spread out from the mean.
What is the difference between sample and population standard deviation?
The sample formula uses n minus 1 in the variance denominator, while the population formula uses n.
Can standard deviation be negative?
No. Standard deviation is always zero or positive.