How To Create A Secondary Axis In Excel

While the secondary vertical axis provides a way to display two different types of data for the one time range, the secondary horizontal axis allows you to create a chart showing two data series for different time ranges.

Two horizontal axes on the same side in Excel 365

By default, Excel creates a chart with the primary horizontal axis at the bottom and with the primary vertical axis at the left side of the plot area (shown as orange in this example). When you add the secondary horizontal axis, Excel adds it to the top of the plot area (shown as blue in the above example). The secondary vertical axis is placed at the right side (shown as blue in the above chart):

Two horizontal axes in Excel 365

See how to add the secondary vertical axis and position both vertical axes on the same side for more details.

Add the secondary horizontal axis

To add a secondary horizontal axis, do the following:

1. Add the secondary vertical axis to any of the data series (see How to create two vertical axes on the same side).

2. Select the data series which you want to see using the secondary horizontal axis.

3. On the Chart Design tab, in the Chart Layouts group, click the Add Chart Element drop-down list:

Add Chart Element button in Excel 365

Choose the Axes list and then click Secondary Horizontal:

Add the Secondary horizontal axis in Excel 365

Excel adds the secondary horizontal axis for the selected data series (on the top of the plot area):

Secondary horizontal axis in Excel 365

5. To see the correct data for the primary and secondary horizontal axes, do one of the following:

On the Chart Design tab, in the Data group, choose Select Data:
Right-click in the chart area and choose Select Data... in the popup menu:

In the Select Data Source dialog box:

Select Data Source in Excel 365

Select the appropriate data series,
Click the Edit button on the Horizontal (Category) Axis Labels area.

The data series will have different Horizontal (Category) Axis Labels to show them on the primary and secondary horizontal axes. For example:

Secondary horizontal axis in Excel 365

Display dual horizontal axis on one side

1. Select the horizontal axis that you want to move to the opposite side of the plot area, right-click on it and choose Format Axis... in the popup menu:

Format Axis popup in Excel 365

2. On the Format Axis pane, in the Axis Options tab, in the Labels section, choose the appropriate option from the Label Position drop-down list:

Label Position in Format Axis pane Excel 365

Next to Axis (used by default) shows the primary horizontal axis on the bottom of the plot area, the secondary horizontal axis on the top of the plot area.
High, shows the primary axis in the highest values of the data, on the top:
Low, shows the secondary axis in the lowest values of the data, on the bottom:
None, hide labels for the axis. You still can select it, change its options, but can't see the labels.