Quartiles & IQR Calculator

Calculate quartiles, interquartile range, detect outliers, and visualize data with box plots.

Enter numbers separated by commas (e.g., 1, 2, 3, 4, 5)

Résultats

Entrez les valeurs et cliquez sur Calculer pour voir le résultat.

Theory & Formula

What are Quartiles?

Quartiles divide the data into four equal parts. They help identify the distribution and spread of data.

The Three Quartiles

Q1: Q1: 25th percentile (25% of data below this value)

Q2: Q2: 50th percentile (median, 50% of data below this value)

Q3: Q3: 75th percentile (75% of data below this value)

Interquartile Range (IQR)

\(IQR = Q_3 - Q_1\)

IQR measures the spread of the middle 50% of data

Outlier Detection

Values outside 1.5 × IQR from Q1 or Q3 are considered outliers

\(\text{Lower bound} = Q_1 - 1.5 \times IQR\)\(\text{Upper bound} = Q_3 + 1.5 \times IQR\)
Quartiles & IQR Calculator | Box Plot & Outlier Detection | MathCalcLab | MathCalcLab