The **standard deviation** is a common way to measure how “spread out” data values are. In statistics, the standard deviation is often referred to as **sigma**, which is written as σ.

Values that lie outside of three sigmas from the mean are often denoted as outliers or unusual values in a dataset. Thus, finding the value of three sigmas from the mean is often of interest to statisticians and researchers.

To find the value of sigma as well as three sigma for a given dataset, enter your comma separated data in the box below, then click the “Calculate” button:

**Standard Deviation (Sigma):** 12.3448

**Three Sigma:** 37.0343

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