Z-Score Calculator
Free online Z-score calculator. Calculate the standard score from raw score, population mean, and standard deviation.
Z-Score Standard Score Calculator
Z-Score: 1.50
What is a Z-Score?
A Z-score (also known as a standard score) is a statistical measurement that describes a value's relationship to the mean of a group of values.
Z-score is measured in terms of standard deviations from the mean. If a Z-score is 0, it indicates that the data point's score is identical to the mean score. A Z-score of 1.0 would indicate a value that is one standard deviation from the mean.
The Z-Score Formula
The standard score is calculated using the formula:
Z = (X - μ) / σ
- Z: The standard score.
- X: The raw data value (the score you are evaluating).
- μ: The population mean.
- σ: The population standard deviation.
How to Interpret Z-Scores?
- Positive Z-score: The raw score is higher than the mean average.
- Negative Z-score: The raw score is lower than the mean average.
- Z-score = 0: The raw score is exactly the same as the mean.