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Often you may want to convert the x-axis or y-axis scale of a ggplot2 plot into a log scale.

You can use one of the following two methods to do so using only ggplot2:

**1. Use scale_y_continuous() or scale_x_continuous()**

ggplot(df, aes(x=x, y=y)) + geom_point() + scale_y_continuous(trans='log10') + scale_x_continuous(trans='log10')

**2. Use coord_trans()**

ggplot(df, aes(x=x, y=y)) + geom_point() + coord_trans(y ='log10', x='log10')

If youâ€™d like to format the axis labels to show exponents, you can useÂ functions from the scales package:

ggplot(df, aes(x=x, y=y)) + geom_point() + scale_y_continuous(trans='log10', breaks=trans_breaks('log10', function(x) 10^x), labels=trans_format('log10', math_format(10^.x)))

This tutorial shows examples of how to use these functions in practice.

**Example 1: Log Scale Using scale_y_continuous()**

The following code shows how to use the **scale_y_continuous()** function to create a log scale for the y-axis of a scatterplot:

library(ggplot2) #create data frame df #create scatterplot with log scale on y-axis ggplot(df, aes(x=x, y=y)) + geom_point() + scale_y_continuous(trans='log10')

**Example 2: Log Scale Using coord_trans()**

The following code shows how to use the **coord_trans()** function to create a log scale for the y-axis of a scatterplot:

library(ggplot2) #create data frame df #create scatterplot with log scale on y-axis ggplot(df, aes(x=x, y=y)) + geom_point() + coord_trans(y='log10')

**Example 3: Custom Log Scale Labels**

The following code shows how to use functions from the **scales** package function to create a log scale for the y-axis of a scatterplot and add custom labels with exponents:

library(ggplot2) library(scales) #create data frame df #create scatterplot with log scale on y-axis and custom labels ggplot(df, aes(x=x, y=y)) + geom_point() + scale_y_continuous(trans='log10', breaks=trans_breaks('log10', function(x) 10^x), labels=trans_format('log10', math_format(10^.x)))

Notice that the y-axis labels have exponents, unlike the previous two plots.

**Additional Resources**

The Complete Guide to ggplot2 Titles

A Complete Guide to the Best ggplot2 Themes

How to Create Side-by-Side Plots in ggplot2