You can use the annotate() function to add text to plots in ggplot2.

This function uses the following basic syntax:

p +
  annotate("text", x=6, y=10, label= "hello")

where:

• x, y: The (x, y) coordinates where the text should be placed.
• label: The text to display.

The following examples show how to use this function in practice.

Example 1: Add One Text Element to ggplot2

The following code shows how to use annotate() to add one text element to a ggplot2 scatterplot:

library(ggplot2)

#create data frame
df <- data.frame(x=c(1, 3, 3, 5, 7, 8, 10, 11),
                 y=c(3, 5, 7, 5, 8, 10, 14, 19))

#create scatter plot with one text element
ggplot(df, aes(x=x, y=y)) +
  geom_point()
  annotate("text", x=6, y=10, label= "hello")

Notice that our text element has been added to the (x, y) coordinates of (6, 10) in the plot.

Example 2: Add Multiple Text Elements to ggplot2

The following code shows how to use annotate() to add multiple text elements to a ggplot2 scatterplot:

library(ggplot2)

#create data frame
df <- data.frame(x=c(1, 3, 3, 5, 7, 8, 10, 11),
                 y=c(3, 5, 7, 5, 8, 10, 14, 19))

#create scatter plot with one text element
ggplot(df, aes(x=x, y=y)) +
  geom_point() +
  annotate("text", x=6, y=10, label= "hello") +
  annotate("text", x=3, y=15, label= "hello again")

Notice that two text elements have been added to the plot at the coordinates that we specified.

Example 3: Customize Text Elements in Plot

library(ggplot2)

#create data frame
df <- data.frame(x=c(1, 3, 3, 5, 7, 8, 10, 11),
                 y=c(3, 5, 7, 5, 8, 10, 14, 19))

#create scatter plot with custom text element
ggplot(df, aes(x=x, y=y)) +
  geom_point() +
  annotate("text", x=6, y=10, label= "bolditalic(hello)",
           col="blue", size=10, parse=TRUE)

Notice that the one text element in the plot is now bold, italic, blue and has a size of 10.

Note: You can find the complete documentation for the annotate() function in ggplot2 .

Additional Resources

The following tutorials explain how to perform other common tasks in R: