What is the Z Score Calculator?
Calculate the z-score of a value from the mean and standard deviation.
Enter value, mean and standard deviation and the Z Score Calculator returns z-score and interpretation. Results update as you type, and nothing you enter leaves your device.
How it is calculated
z = (x − μ) ÷ σ
How to use it
- Enter value.
- Enter mean.
- Enter standard deviation.
- Read z-score in the results panel. It updates as you type.
- Change any value to compare scenarios, or use Share to send the result as a link.
Worked example
Common questions
What formula does the Z Score Calculator use?
It uses: z = (x − μ) ÷ σ.
What do I need to use the Z Score Calculator?
You need value, mean and standard deviation. Sensible starting values are filled in so you can see how it works straight away.
Is the Z Score Calculator free, and is my data stored?
It is free with no sign-up. The calculation runs in your browser, so the values you enter are not sent to or stored on our server.