increase legend font size ggplot2

Solution 1:

You can use theme_get() to display the possible options for theme. You can control the legend font size using:

+ theme(legend.text=element_text(size=X))

replacing X with the desired size.

Solution 2:

theme(plot.title = element_text(size = 12, face = "bold"),
    legend.title=element_text(size=10), 
    legend.text=element_text(size=9))

Solution 3:

You can also specify the font size relative to the base_size included in themes such as theme_bw() (where base_size is 11) using the rel() function.

For example:

ggplot(mtcars, aes(disp, mpg, col=as.factor(cyl))) +
  geom_point() +
  theme_bw() +
  theme(legend.text=element_text(size=rel(0.5)))

Solution 4:

A simpler but equally effective option would be:

+ theme_bw(base_size=X)