# How to Make a Box and Whisker Plot

If you’d like to know how to make a box and whisker plot, you’re in the right place. One of the most common uses of the five-number summary is the graph called a “box plot” or “box and whisker plot.” It’s a great way to get a visual look at the five number summary.

## Basics

To make a box and whisker plot, you’ll need to have the five number summary: minimum, first quartile, median, third quartile, and maximum (these are also known as quartiles). Read more about quartiles, and check out our statistics video lessons for even more statistics topics!

Box and whisker plots can be drawn horizontally or vertically. For illustration purposes, we’ll draw one horizontally. It’s the same steps to draw one vertically—just rotated 90 degrees!

The basic idea is to draw a rectangle (the “box”) to represent the middle 50% of a group of numbers, and then one line (or “whisker”) on either side of the box to represent the top 25% and bottom 25%. Let’s look at an example.

## Example of How to Make a Box and Whisker Plot

So, we begin with our five numbers, which summarize a set of data. Let’s say we’re looking at a set of SAT math scores, with a five number summary of 250, 400, 500, 560, and 720.

That means that the lowest score in this group was 250 and the highest score was 720 (the minimum and maximum). The median, 500, means that half the group scored above 500 and the other half below 500. And the quartiles separate out the lowest and highest 25% of the group—so a quarter of the group scored below 400 and a quarter scored above 560.

(Want to read more about the difference between median, mean, and other “averages”? Here’s a quick rundown on mean, median, and mode.)

## Step by Step Instructions

Start with an axis, or number line, to give a reference point. You can either label the axis fully, or just label each of the five numbers on the axis. Now make a small vertical line above each of the five numbers. These should float a bit above your axis, and not touch the axis. Next, draw the “box” with horizontal lines connecting the tops and bottoms of the first and third quartile marks. Finally, create the “whiskers.” Draw one line from the middle of the third quartile mark to the maximum mark, and another line from the middle of the minimum mark to the first quartile mark. That’s it! Give your graph a title and make sure that the axis is labeled. You’ve created a box and whisker plot! You can see where each of the five numbers from the five number summary are, and can easily compare two groups side-by-side. 