Average Calculator: Mean, Median, Mode and Range Explained
The average of a data set can mean several different things. This calculator returns the mean, median, mode and range together, because looking at all four is the only way to tell whether a single 'average' is actually describing your numbers fairly.
Which average to use
- Mean — add all values and divide by the count. Best for symmetric data with no extreme outliers.
- Median — the middle value when sorted. Best for skewed data such as income, house prices or response times.
- Mode — the most frequent value. The only average that works for categories.
- Range — highest minus lowest. A one-number measure of spread.
Why outliers matter
In the set 30,000, 32,000, 35,000, 38,000 and 900,000, the mean is over 200,000 while the median is 35,000. The median describes a typical member of that group; the mean does not. Whenever a distribution has a long tail, report the median, and consider reporting both so readers can see the skew.
Weighted averages
When values do not carry equal importance — course credits, portfolio positions, survey strata — multiply each value by its weight, sum the results and divide by the total weight. Treating a weighted set as a simple mean is a frequent source of wrong grade and portfolio figures.
Key takeaways — Average Calculator
- Mean, median and mode answer different questions about the same data.
- Use the median when outliers or skew are present.
- Pair any average with a measure of spread such as range or standard deviation.