Four numbers that describe a list
The mean, median, mode and range are the first things people work out about a set of numbers. The mean is the average, the median is the middle value, the mode is the value that appears most often and the range is the gap between the largest and smallest.
Type your numbers and this calculator shows all four, along with the count, the sum, and the working so you can follow the method.
How it is calculated
Worked example
Data: 5, 8, 12, 8, 3, 20, 8
- Sorted
- 3, 5, 8, 8, 8, 12, 20
- Mean
- 9.1429
- Median
- 8
- Mode
- 8
- Range
- 17
When each one is best
| Measure | Best for | Weakness |
|---|---|---|
| Mean | Symmetric data | Pulled by outliers |
| Median | Skewed data such as incomes | Ignores the exact values |
| Mode | Most popular choice | May not exist or may repeat |
| Range | Quick idea of spread | Uses only two values |
When each measure misleads
The mean is pulled by extreme values (a single very high salary skews a team's average pay upward). The mode can be meaningless for continuous measurements like height, where almost every value is unique. The range uses only the two extreme values, ignoring everything in between — a data set with one outlier can have a huge range despite most values being close together.