Z-score Calculator

Calculate Z-score

Value (X)

Population Mean (μ)

Standard Deviation (σ)

Results

Enter values and click calculate to see results

Understanding Z-scores

What is a Z-score?

Measures distance from mean
In standard deviation units
Shows relative position
Standardizes comparisons

Interpretation

0 = exactly at mean
±1 = typical range
±2 = unusual
±3 = very unusual

Common Uses

Test scores
Quality control
Research analysis
Performance evaluation