Calculate Q1, Q2 (median), and Q3 quartiles from a set of numbers.
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Enter your numbers separated by commas.
Q1 = 25th percentile
Q2 = 50th percentile (median)
Q3 = 75th percentile
IQR = Q3 − Q1
Quartiles divide sorted data into four equal parts. The interquartile range (IQR) measures spread.
Enter values to calculate.
Values that divide a sorted dataset into four equal parts. Q1 is the 25th percentile, Q2 is the median, Q3 is the 75th.
The interquartile range (Q3−Q1) measures data spread. Values beyond 1.5×IQR from Q1 or Q3 are potential outliers.
Quartiles are specific percentiles: Q1=P25, Q2=P50, Q3=P75. Percentiles offer finer granularity.
Quartiles are meaningful with at least 4 values but more reliable with 20+. Small datasets produce unstable estimates.