Standard Deviation & Z-Score Calculator
Enter a dataset and get the mean, variance, standard deviation, and Z-score percentile instantly
Paste in a set of numbers and instantly get the mean, variance, and population standard deviation — plus the Z-score and percentile for any value you're checking against the distribution.
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How to use
- Enter numbers separated by commas.
- Read the mean, standard deviation, and variance.
FAQ
- Is this the sample or population standard deviation?
- By default it shows the population standard deviation (dividing by N).
- Is there a limit on how many numbers I can enter?
- There's no hard limit on how many comma-separated values you can enter, but for readability it's best to keep it to a few dozen numbers at a time.
- How much does a single outlier skew the result?
- Because standard deviation squares each value's distance from the mean, even one extreme outlier can significantly distort the variance and standard deviation — it's worth checking your data for outliers first.