Z-Score Calculator
Find how many standard deviations a value is from the mean.
For statistical guidance only; use with appropriate data.
Examples
- Value 85, mean 70, SD 10 ⇒ 1.5 z
- Value 60, mean 50, SD 5 ⇒ 2 z
FAQ
What is a z-score?
It expresses how far a value is from the mean in standard deviations.
Can standard deviation be zero?
No, a zero standard deviation would make the calculation invalid.
How is the z-score used?
It's used to compare values across different distributions.
Does the sign matter?
Yes, positive means above the mean, negative below it.
Additional Information
- Widely used in statistics to standardize values for comparison across different normal distributions.
- A negative z-score indicates the value lies below the mean, while a positive score means it's above.