Microsoft Excel contains a powerful graph utility that can make professional-looking charts in seconds. A logarithmic scale is a scale that represents the logarithm of a quantity instead of the quantity itself. Logarithms can come in handy when referencing a large range of values on a graph. Although you can create a variety of graphs in Excel, the only chart type that supports log-log graphs, where logarithmic scales are on both the y- and x-axis, is the scatter graph.
Highlight the data on the datasheet by clicking at the top left and then dragging the cursor to the bottom right.
Click "Insert" and then click "Scatter." Click the first scatter icon and Excel inserts a scatter chart into your spreadsheet.
Right-click the scale of the x-axis and then click "Format Axis." Click the "Axis Options" tab and then click the "Logarithmic Scale" check box.
Right-click the scale of the y-axis and then click "Format Axis." Click the "Axis Options" tab and then click the "Logarithmic Scale" check box.
In previous versions of Excel, the "Logarithmic Scale" check box is located in the "Format Axis" box on the "Scale" tab.