How to Use Secondary Axis in Chart in Excel Easily

To use a secondary axis in an Excel chart, first create your chart with multiple data series. Then, right-click the data series you want on the secondary axis, select Format Data Series, and choose Secondary Axis. This lets you compare data with different scales clearly.

Syntax

In Excel, there is no formula syntax for adding a secondary axis; it is done through the chart interface. The key steps are:

• Create a chart with multiple data series.
• Select a data series to plot on the secondary axis.
• Right-click the series and choose Format Data Series.
• Choose the Secondary Axis option.

This moves the selected series to a new vertical axis on the right side of the chart.

excel

1. Insert chart with multiple data series
2. Right-click data series to move
3. Click 'Format Data Series'
4. Select 'Secondary Axis'
5. Close the pane and view updated chart

Example

This example shows how to add a secondary axis to a chart comparing sales and profit margin, which have different scales.

excel

1. Enter data in Excel:
   A1: Month, B1: Sales, C1: Profit Margin
   A2: Jan, B2: 10000, C2: 0.25
   A3: Feb, B3: 15000, C3: 0.30
   A4: Mar, B4: 12000, C4: 0.28

2. Select A1:C4
3. Insert a 'Line with Markers' chart
4. Right-click the 'Profit Margin' line
5. Choose 'Format Data Series'
6. Select 'Secondary Axis'
7. Close the pane

The chart now shows Sales on the left axis and Profit Margin on the right axis.

Output

Chart with two lines: Sales scale on left vertical axis, Profit Margin scale on right vertical axis

Common Pitfalls

• Not selecting the correct data series: Make sure you right-click the exact series you want on the secondary axis.
• Using incompatible chart types: Some chart types do not support secondary axes well, like pie charts.
• Confusing axis labels: Always check that axis titles clearly show which axis belongs to which data.
• Overcrowding the chart: Too many series on secondary axis can make the chart hard to read.

excel

Wrong way:
- Trying to add secondary axis by selecting the whole chart and formatting

Right way:
- Right-click the specific data series > Format Data Series > Secondary Axis

Quick Reference

Step	Action
1	Create chart with multiple data series
2	Right-click data series to move
3	Select 'Format Data Series'
4	Choose 'Secondary Axis' option
5	Review chart with two vertical axes

Key Takeaways

Right-click the specific data series to assign it to the secondary axis.

Secondary axis helps compare data series with different scales clearly.

Use compatible chart types like line or column charts for secondary axes.

Label both primary and secondary axes to avoid confusion.

Avoid cluttering the chart with too many series on the secondary axis.