How to Create a Log-Log Plot in Excel

log-log plot is a scatterplot that uses logarithmic scales on both the x-axis and the y-axis.

This type of plot is useful for visualizing two variables when the true relationship between them follows a power law. This phenomenon occurs in many fields in real life including astronomy, biology, chemistry, and physics.

This tutorial shows how to create a log-log plot for two variables in Excel.

Example: Log-Log Plot in Excel

Suppose we have the following dataset in Excel that shows the values for two variables, x and y:

Use the following steps to create a log-log plot for this dataset:

Step 1: Create a scatterplot.

Highlight the data in the range A2:B11

Along the top ribbon, click the Insert tab. Within the Charts group, click on Scatter.

The following scatterplot will automatically appear:

Step 2: Change the x-axis scale to logarithmic.

Right click on the values along the x-axis and click Format Axis.

In the new window that pops up, check the box next to Logarithmic scale to change the x-axis scale.

Log-scale for plot in Excel

Step 3: Change the y-axis scale to logarithmic.

Next, click on the y-axis and repeat the same step to change the y-axis scale to logarithmic. The resulting plot will look like this:

Log-log plot in Excel

Notice that the x-axis now spans from 1 to 10 while the y-axis spans from 1 to 1,000. Also notice how the relationship between the variables x and y now appears more linear. This is an indication that the two variables do indeed have a power law relationship.

You can find more Excel tutorials here.

One Reply to “How to Create a Log-Log Plot in Excel”

  1. Hi,

    I’m trying to perform an assay that requires me to do a log-log linear regression. I was able to produce the log-log graph on excel, but when fitting with a linear trend line, the line appears not to be linear even though the data points are.
    Is there a way to fix this, or a reason this is happening?

    Thank you

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