You enter a list of comma-separated numbers and optional weights. The tool parses the list, then computes seven averages using their standard mathematical definitions: arithmetic mean (sum divided by count), weighted mean (weighted sum divided by weight total), median (middle of sorted values), mode (highest-frequency value), geometric mean (nth root of product), harmonic mean (count divided by reciprocal sum), and RMS (square root of mean of squares). Non-positive values are excluded from the geometric mean; zeros are excluded from the harmonic mean.
Use the median when your data has extreme outliers or is skewed. For example, household income data is typically reported as median because a few very high earners pull the mean upward, making it less representative of the typical value.
Weights let you give some values more importance than others. A common example is calculating a GPA, where each course grade is weighted by its credit hours. Leave weights blank for an equally-weighted average.
The geometric mean requires all values to be positive (greater than zero). If your data set includes zero or negative numbers, the geometric mean is mathematically undefined and will show a dash instead.
Root Mean Square gives higher weight to larger values and is used in engineering and physics — for example, AC voltage is expressed as an RMS value. It is always equal to or greater than the arithmetic mean.
Estimate only. Results reflect your inputs and standard formulas. Double-check important decisions independently.