What is a Stem and Leaf Plot?

Everything You Need to Know About Stem and Leaf Plots—Simple Definition and Examples

Whenever you are dealing with numbers and data, it is helpful to be able to organize and display the data in ways that are clear and easy to analyze and draw conclusions from. One extremely useful tool for organizing data in such a way is called a steam and leaf plot, which is a visualize tool that allows you to easily identify the distribution of values in a given data set as well as any patterns or trends that may be present.

This free guide will teach you everything you need to know about stem and leaf plots, including a simple definition, how to make a stem and leaf plot, and examples. You can follow each section of this guide in order or you can click on any of the text links below to jump to a section of interest:

Simple Definition of Stem and Leaf Plots
What is a Stem and Leaf Plot?
How to Make a Stem and Leaf Plot
Stem and Leaf Plot Examples (including Decimals)

Let’s begin by learning a simple definition of stem and leaf plots and what they represent.

Simple Definition of Stem and Leaf Plots

What is a stem and leaf plot and what does it look like?

Definition: In math, a stem and leaf plot is a simple chart that can be used to organize the distribution of numbers in a data set. The name “stem and leaf plot” refers to two parts of the simple chart: the “stem” representing the first (and larger) part of the numbers, and the “leaf” representing the second (and smaller) part of the numbers.

For example, let’s say that we want to organize the following data set using a stem and leaf plot:

Data Set: 14, 19, 22, 24, 24, 28, 30, 36, 44, 49, 57

The diagram in Figure 01 below displays the stem and leaf plot that corresponds with this data set:

What is a Stem and Leaf Plot?

Take a close look at the stem and leaf plot in Figure 01 above.

Notice that a steam and leaf plot has two columns:

Left Column: This column represents the stem, or the larger part of each number.
Right Column: This column represents the leaf, or the smaller part of each number.

For example, to “place” the number 36 into the stem and leaf plot in Figure 01, you would have to split 36 into two parts (the stem and the leaf) as follows:

Stem: 30
Leaf: 6

In other words, Stem = 3 and Leaf = 6 means that the number being represented in the stem and leaf plot is 36.

Similarly,

Stem = 1 and Leaf = 9 → 19
Stem = 2 and Leaf = 4 → 24
Stem = 4 and Leaf = 4 → 44
Stem = 4 and Leaf = 9 → 49
Stem = 5 and Leaf = 7 → 57

This process applies to all of the numbers in the data set. Now, let’s go ahead and learn how to make our own stem and leaf plot.

How to Make a Stem and Leaf Plot

In this next section, we will learn how to make a stem and leaf plot that represents the distribution of ages of members of Maria’s family members.

In order to make a stem and leaf plot, we will need a data set. In this case the data set that we will be using contains values that represent the ages of the members of Maria’s family:

Ages of Maria’s Family Members: 16, 17, 21, 23, 30, 33, 37, 38, 38, 42, 45, 50, 56, 57, 64, 79, 83

By looking at the data values, we can see that the ages range from 16 to 83 and that each number has two values. So, in this case, the first value of each number (the value in the tens place value slot) will be our stem, and the second value of each number (the value in the ones place value slot) will be our leaf.

All stem and leaf plots will have two columns. However, the number of rows will depend on the data. In this example, we have 8 different first digits, so we will need 8 rows.

How to Make a Stem and Leaf Plot: Step #1: Draw a blank table that corresponds with the given data set.

Figure 03 below illustrates this first step. We now have two-column table (the left column is labeled “stem” and the right column is labeled “leaf”) with 8 rows (one for each stem value: 1, 2, 3, 4, 5, 6, 7, and 8).

How to Make a Stem and Leaf Plot: Step #2: Complete the leaf column for each stem value.

Now that we have our table, we can begin the process of completing our stem and lead plot. We can start with the first row, which is where we will place all of the numbers in the data set that start with 1 (in this case, we have to place the numbers 16 and 17).

16 → Stem = 1 and Leaf = 6
17 → Stem = 1 and Leaf = 7

This means that in our first row where the stem value is 1, we have to write the numbers 6 and 7 in the leaf column directly to the right as shown in Figure 04 below.

Pretty simple, right? To complete this stem and leaf plot, you will repeat this process for all of the remaining rows.

For example, the second row has two values: 21 and 23:

21 → Stem = 2 and Leaf = 1

23 → Stem = 2 and Leaf = 3

The third row has five values: 30, 33, 37, 38, and 38:

30 → Stem = 3 and Leaf = 0
33 → Stem = 3 and Leaf = 3
37 → Stem = 3 and Leaf = 7
38 → Stem = 3 and Leaf = 8
38 → Stem = 3 and Leaf = 8

Notice that the number 38 appears twice (since two family members are 38 years old), which means that we have to include the leaf of 8 twice.

The fourth row has two values: 42 and 45:

42 → Stem = 4 and Leaf = 2

45 → Stem = 4 and Leaf = 5

Continue this process for each row until you have completed your stem and leaf plot. The graphic in Figure 05 below shows what the completed stem and leaf plot representing the ages of Maria’s family members.

Stem and Leaf Plot Examples

So far in this guide, we have taken a deep dive into stem and leaf plots, including a simple definition of stem and leaf plots and how to make a stem and leaf plot and how to read a stem and leaf plot.

Finally, we can take a look at a few stem and leaf plot examples.

Stem and Leaf Plot Example #1: Tina recorded number of miles driven each week over a three-month span:

Weekly Miles Driven: 26, 27, 28, 29, 30, 32, 32, 32, 45, 46, 47, 59

The stem and leaf plot that represents this data is shown in Figure 06 below.

Are you starting to get the hang of how to make a stem and leaf plot and how to read a stem and leaf plot?

Let’s take a look at one final example that includes decimal numbers.

Stem and Leaf Plot Example #2: Rafael recorded the heights of several seedlings one month after planting them:

Seedling Heights (in inches): 3.2, 3.5, 3.7, 4.0, 4.6, 4.9, 5.3, 5.3, 6.1

In the case of decimal numbers, the stem value will be the whole number portion of the data value (the number on the left of the decimal point) and the leaf value will be the decimal portion of the data value (the number on the right of the decimal point).

For example: