What is the five-number summary?

It is a set of five descriptive statistics: minimum, first quartile (Q1), median (Q2), third quartile (Q3), and maximum. Together they describe the distribution of a dataset concisely.

What quartile method does this tool use?

This tool uses the inclusive (Tukey) method, which is standard in most textbooks and matches Excel's QUARTILE.INC function.

The Interquartile Range (IQR) equals Q3 minus Q1. It represents the middle 50% of the data and is used to detect outliers: values below Q1 - 1.5*IQR or above Q3 + 1.5*IQR are considered potential outliers.

How many numbers do I need?

You need at least two numbers. With a single number, all five values collapse to the same point. With more data points you get a more meaningful summary.

No. The tool automatically sorts your input in ascending order before computing statistics.

Five Number Summary Calculator

Name: Five Number Summary Calculator
Availability: InStock
Author: Nham Vu

Enter a dataset and instantly compute the five-number summary: minimum, Q1, median, Q3, maximum, and IQR.

Enter Your Dataset

Numbers (comma or newline separated)

Load sample dataset

Enter numbers on the left and click Calculate

Results will appear here

Five-Number Summary

Statistic	Symbol	Value

Sorted Dataset

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Summary

Enter a dataset and instantly compute the five-number summary: minimum, Q1, median, Q3, maximum, and IQR.

How it works

Enter your numbers separated by commas or newlines.
The tool sorts the dataset in ascending order.
It applies the inclusive (Tukey) quartile method to find Q1, the median, and Q3.
Minimum and maximum are read from the ends of the sorted list.
IQR is computed as Q3 minus Q1 and used for the 1.5*IQR outlier rule.

Use cases

Summarize a dataset before running further statistical analysis.
Identify the spread and center of exam scores or survey responses.
Detect potential outliers using the 1.5 * IQR rule.
Build box plots — they require exactly the five-number summary.
Compare distributions across multiple groups in research.

Frequently Asked Questions

Last updated: 2026-06-10 · Reviewed by Nham Vu