IQR Calculator
Calculate the interquartile range — the spread of the middle 50% of your data.
Calculate
Enter your values below.
Result
IQR
0
Formula used
IQR = Q3 − Q1
Example: 1-10 → Q1 = 3.25, Q3 = 7.75, IQR = 4.5.
How to use this calculator
- Enter Numbers (comma-separated).
- Press Calculate to see your result instantly.
FAQ
Frequently asked questions
What does IQR measure?
The range covered by the middle 50% of the data, ignoring the top and bottom quarters.
Why use IQR instead of range?
IQR is less sensitive to outliers than the full range, since it ignores the most extreme values.
How is IQR used to detect outliers?
Values below Q1 − 1.5×IQR or above Q3 + 1.5×IQR are commonly flagged as outliers.
Where can I see Q1 and Q3 separately?
Use the Quartile Calculator for the full breakdown.