Interquartile Range (IQR) Calculator
Calculate the interquartile range and detect outliers using the IQR method. Enter Q1 and Q3 to find the IQR, outlier fences, and mid-hinge.
The interquartile range (IQR) is a robust measure of statistical dispersion.
Formula: IQR = Q3 - Q1
Outlier Fences:
- Mild outlier: value < Q1 - 1.5×IQR or value > Q3 + 1.5×IQR
- Extreme outlier: value < Q1 - 3×IQR or value > Q3 + 3×IQR
Advantages of IQR:
- Not affected by extreme outliers (unlike range or standard deviation)
- Works well with skewed distributions
- Used in box plots for visualization