Standard Deviation Calculator

A professional-grade analyzer for measuring data dispersion.

Dataset Input

Enter data values (separated by commas, spaces, or semicolons) Example: 45, 12, 88, 34, 56, 12

Statistical Profile

Sample Standard Deviation (s)

Population Std Dev (σ): --

Count (N)

Sum

Mean (x̄)

Standard Deviation

Variance (s²)--

Best for analyzing a subset of a larger population. Uses N-1 denominator.

Standard Deviation

Variance (σ²)--

Use only when your dataset represents the entire group. Uses N denominator.

Help & Theory

Enter your series of numbers into the text area. We'll automatically parse the list and calculate the mean and standard deviation for you.

Mean: The arithmetic average of all points.
Variance: The average of the squared differences from the mean.
Sigma (σ): The population standard deviation symbol.

In a typical distribution, 68% of your values should lie within one standard deviation of the mean.

If your dataset is very small, the Sample standard deviation will be significantly higher than the Population version due to "Bessel's Correction" (the N-1 factor), which accounts for the uncertainty in small samples.

Standard Deviation Calculator

General Summary

Sample Mode

Population Mode

Key Terms

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Expert Note

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