Statistics
Z-score and normal distribution calculator
Calculate how many standard deviations a value is from the mean and estimate its percentile in a normal distribution.
Z-score
1.5
Approximate percentile
93.319%
Area on the right
6.681%
Standard normal distribution
The displayed percentile assumes a normal distribution. If the actual data do not follow that distribution approximately, the interpretation may change.
Frequently asked questions
What does a Z-score indicate?
It measures how many standard deviations a value is above or below the average.
What does a positive Z-score mean?
It means the value is above the mean. A negative value means it is below.
Is the percentile always accurate?
Only under the assumption of a normal distribution with the mean and standard deviation indicated.