Skewness Calculator

This skewness calculator works out the moment coefficient of skewness for any data set you enter, showing how asymmetric your numbers are around their average. Type in a list of values separated by commas, for example test scores, wait times or income figures, and the calculator instantly returns three results: the skewness value, the mean of your data, and the sample size, the count of numbers entered. A skewness of zero means your data is symmetric, spread evenly either side of the mean, much like the normal distribution. A positive value shows a long tail stretching to the right, where a few unusually large values pull the mean upward, while a negative value shows the opposite, a long tail to the left dragging the mean down. This matters because skewed data can make the mean misleading as a typical figure, in which case the median often describes the centre more fairly. The calculator uses the population standard deviation in its formula, the average of each value's deviation from the mean cubed, divided by the standard deviation cubed, then rounds results for easy reading. Below the calculator you will find the formula explained, a worked example using a symmetric data set to confirm a skewness of zero, and answers to common questions about interpreting positive, negative and zero skew for statistics assignments, research or everyday data analysis.

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