A z-score tells you how many standard deviations away an individual data value falls from the mean. It is calculated as:
z-score = (x – μ) / σ
where:
- x: individual data value
- μ: population mean
- σ: population standard deviation
This calculator allows you to compare the relative standing of two data points using their z-scores. Simply fill in the boxes below and then click the “Calculate” button.
z-score of first value = (19–15) / 4.2 = 0.9524
z-score of second value = (17–14) / 2.6 = 1.1538