Interquartile Range Calculator
Math
Calculate interquartile range with explicit inputs and a worked example.
Formula
IQR = Q3 − Q1
- Use the units shown beside each field.
- Results update automatically whenever you change an input.
- Displayed values use up to four decimal places, or scientific notation for very small or large numbers. Calculations use standard floating-point arithmetic; exact integer and fraction tools identify their own precision rules.
- Uses the R-7 quantile convention.
Example Calculation
Example inputs
- Data: 1, 2, 3, 4, 5
For 1,2,3,4,5, Q1=2 and Q3=4, giving IQR=2.
Frequently asked questions
How do I use this calculator?
Enter data. The result updates automatically. Use Reset to restore the example values.
What method does it use?
IQR = Q3 − Q1. Uses the R-7 quantile convention.
Why might a rounded result differ?
The calculation keeps full numeric precision internally, then rounds the displayed result. Rounding intermediate steps by hand can produce a slightly different answer.
Are my inputs saved online?
No. This calculator processes your inputs in your browser. A recently used list stores only calculator names on this device, not your entered values.
Check the assumptions and units before using this result. Read about calculation methods.