How to change the default font size in ggplot2

Use theme_set()

theme_set(theme_gray(base_size = 18))qplot(1:10, 1:10)

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r ggplot2 default font-size

Use theme_set if you want to update for the remainder of your active session:

theme_set(theme_grey(base_size = 18))

If you only want to change one graph you can set the base_size in the theme:

qplot(1:10, 1:10) + theme_grey(base_size = 18) ggplot(mtcars, aes(x = mpg, y = cyl)) + geom_point() +theme_grey(base_size = 18)

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