How to find the range
Sort the numbers (or just scan for the extremes), then subtract the smallest from the largest. For 14, 22, 9, 31, 18, 27 the range is 31 − 9 = 22.
Limits of the range
Because it uses only two values, one unusual measurement changes the range completely. For a spread measure that ignores the extremes, use the interquartile range; for one that uses every value, use the standard deviation. A rough rule of thumb for bell-shaped data is SD ≈ range ÷ 4.
Frequently asked questions
Can the range be negative?
No. The maximum is always at least as large as the minimum, so the range is zero or positive.
What is the range of a function?
That is a different idea from algebra: the set of possible output values. This calculator finds the statistical range of a data set.