Statistics & Probability
Z-Score
Standard score of a value.
Formula
Formula
z = x − μσ
Variables
| Symbol | Definition | Type & range | Units | Role |
|---|---|---|---|---|
| x | value | real number (ℝ) | — | input |
| μ | mean | computed result | — | result |
| σ | std deviation | computed result | — | result |
Try it yourself
Interactive calculator
Worked examples
Example 1
Givenx = 85, mean μ = 70, std σ = 10
Result1.5
Example 2
Givenx = 60, mean μ = 70, std σ = 5
Result-2