Z-score Calculator
Z-score from mean and SD.
Result
Z-score
1
Common questions
What is a Z-score?
A Z-score tells you how many standard deviations a data point is from the mean. Z = (X − μ) ÷ σ. A Z-score of 2 means the value is 2 standard deviations above the mean.
What Z-score corresponds to a 95% confidence level?
A Z-score of 1.96 corresponds to a 95% confidence interval (two-tailed). For 99% confidence, use 2.576. For 90%, use 1.645.