Measure how far a data set spreads from its mean and inspect every squared deviation.
Calculate with the Standard Deviation Calculator
Enter the values below. Invalid mathematical operations are explained before a result is shown.
Standard Deviation Calculator results
Parabola graph
How to use the Standard Deviation Calculator
- Choose a calculation mode when one is available.
- Enter the required values using the examples and field notes as a guide.
- Select Calculate or press Enter.
- Review the primary result, supporting values, and working.
Worked example
For 2,4,4,4,5,5,7,9 the population standard deviation is 2.
Assumptions
The calculator uses real-number arithmetic unless complex square or quadratic roots are explicitly shown. Decimal displays can be rounded while calculations retain normal browser numeric precision.
Limitations
- Sample mode requires at least two values.
- The calculator describes the entered data and does not assume a normal distribution.
Frequently asked questions
Does the Standard Deviation Calculator accept decimals and negative values?
It accepts them wherever the selected operation permits. Invalid domains are identified before a result is shown.
How are decimal results rounded?
Calculations retain JavaScript numeric precision and display a readable number of significant digits. A displayed decimal may therefore be rounded.
Are entries stored?
No. The calculation runs in your browser and this page does not store the values you enter.