About this calculator
The calculator also gives the mid-range and the coefficient of range, a relative measure used to compare spreads in different units.
How to use it
- Enter the numbers.
- Read the range and related measures.
The formula
Range = largest − smallest; coefficient of range = (L − S) ÷ (L + S)
- L
- largest value
- S
- smallest value
Worked example
Marks 23, 17, 41, 9, 35, 28, 12
- Largest 41, smallest 9.
- Range = 32; coefficient of range = 32 ÷ 50 = 0.64.
What the result means
A large range means the values are widely spread, but it depends only on the two extremes, so one unusual value changes it a lot.
Assumptions
- Real numbers.
Limitations
- For a measure that ignores extremes, use the interquartile range.
Frequently asked questions
How do you find the range?
Subtract the smallest value from the largest.
Can the range be negative?
No. It is zero when all values are equal and positive otherwise.
Why is the range a weak measure?
It uses only two values and ignores how the rest are spread.
Last reviewed on 6 October 2026. Found a mistake? Tell us.