Z-Score Calculator
z = (x − mean) / SD. Standard deviation cannot be 0.
Rated 4.7 out of 5 based on 340 reviews
How to use Z-Score Calculator
- Enter value x, mean, standard deviation. Leave a field blank only when the page says the value is missing.
- Read the result rows under the form. Errors appear in the status line. Nothing is uploaded.
- Rounding follows IEEE floating point in this browser unless the page says it uses integers or BigInt.
Z-Score Calculator
z-score
| Computes | z = (x − mean) / SD. Standard deviation cannot be 0. |
|---|---|
| Includes | z-score |
| Includes | Typed mean and SD |
| Engine | stats |
| Upload | None |
| Advice | Arithmetic only |
What Z-Score Calculator is
A z-score says how many standard deviations x sits from the mean. z = 1 is one SD above. This page does not look up a normal table; it returns z only.
The formula runs in this tab. CZNull does not receive the numbers.
How this page computes
Compute mean and SD from a list on standard deviation, then paste them here.
Entities and related jobs
z = (x − mean) / SD. Standard deviation cannot be 0. Named features: z-score, Typed mean and SD.
See also Standard Deviation Calculator, Average Calculator, Variance Calculator, Median and Mode.
Use cases
Comparing scores from tests with different scales. It is not a p-value calculator.
Limits
Invalid input appears in the status line. IEEE floating point applies unless a row says otherwise. CZNull does not receive the numbers.