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