How to Add Titles to Plots in Base R (With Examples)

You can use the title() function to quickly add a title to a plot in base R.

This function uses the following basic syntax:

#create scatterplot of x vs. y
plot(df$x, df$y)

#add title
title('This is my title')

You can also use the following arguments in the title() function to customize the appearance of the title:

col.main: The color of the title
cex.main: The size of the title relative to the default size
font.main: The font style to use for the title (1=plain, 2=bold, 3=italic, 4=bold italic)
adj: The horizontal location of the title (0=left, 1=right, default is 0.5)
line: The vertical location of the title (positive values move title up, negative values move title down)

The following example shows how to use the title() function in practice.

Example: How to Add Title to Plots in Base R

Suppose we use the plot() function in base R to create a simple scatterplot:

#create data frame
df <- data.frame(x=c(70, 78, 90, 87, 84, 85, 91, 74, 83, 85),
                 y=c(90, 88, 79, 86, 84, 83, 88, 92, 76, 75))

#create scatterplot of x vs. y
plot(df$x, df$y, pch=16)

By default, base R does not add a title to the plot.

However, we can use the title() function to quickly add a title:

#create data frame
df <- data.frame(x=c(70, 78, 90, 87, 84, 85, 91, 74, 83, 85),
                 y=c(90, 88, 79, 86, 84, 83, 88, 92, 76, 75))

#create scatterplot of x vs. y
plot(df$x, df$y, pch=16)

#add title
title('Plot of X vs. Y')

Notice that a title has been added to the plot.

We can customize the appearance of the title by using various arguments:

#create data frame
df <- data.frame(x=c(70, 78, 90, 87, 84, 85, 91, 74, 83, 85),
                 y=c(90, 88, 79, 86, 84, 83, 88, 92, 76, 75))

#create scatterplot of x vs. y
plot(df$x, df$y, pch=16)

#add title with custom appearance
title('Plot of X vs. Y', col.main='blue', cex.main=2, font.main=4, adj=0, line=0)