Mean, Median and Mode Calculator

About the Mean, Median and Mode Calculator

The Mean, Median and Mode Calculator describes a list of numbers. The mean is the sum divided by the count, the median is the middle number of the sorted list (or the average of the two middle numbers when the count is even), and the mode is the number that appears most often. If several numbers tie for most often, they are all listed, and if every number appears once there is no mode. The range is the largest minus the smallest. The quartiles are the medians of the lower and upper halves of the sorted list, leaving out the middle number when the count is odd, and the interquartile range is Q3 minus Q1. Other programs use other quartile methods, so a spreadsheet may give slightly different values. Variance is the average squared distance from the mean, and the standard deviation is its square root. The population version divides by n and the sample version divides by n minus 1, which is what to use when the numbers are a sample of a larger group. The tool reads every number as an exact decimal and sums whole numbers, so there is no floating point error, and rounds once at the end, half away from zero, to the number of decimal places you choose. On 20,000 random lists the results matched Python's exact fraction arithmetic in every statistic. Everything runs in your browser and nothing is uploaded.