How are outliers shown on a box plot?

In a box-and-whisker plot, outliers are represented as individual data points, typically marked by dots or asterisks.12

While the standard whiskers of the plot generally extend to the smallest and largest values within a data set, they are adjusted when outliers are present. In such cases, the whiskers extend only to the most extreme values that are not considered outliers, while the outliers themselves are plotted separately beyond the whiskers to highlight their position relative to the rest of the data.2

Identifying these values is a critical step in exploratory data analysis, as statisticians must carefully review them to ensure they are accurate and appropriate for inclusion in the data set.32