How to Merge Graphs in Excel

Combining multiple Excel charts into a single, cohesive visual can transform your report from a simple data dump into a compelling story. A merged graph allows you to directly compare different datasets, show correlations, and save valuable space in your dashboards. This guide will walk you through a few practical methods to merge graphs in Excel, from simple combination charts to clever overlay techniques.

Why Merge Graphs in the First Place?

Before we jump into the "how," let's quickly cover the "why." Merging graphs isn't just about making your spreadsheet look tidier, it's about providing deeper insights more efficiently. The right combination can instantly reveal relationships that would be hard to spot if the charts were separate.

Here are a few common scenarios where merging graphs is incredibly useful:

• Comparing Metrics with Different Scales: You might want to compare website sessions (in the thousands) with the conversion rate (a percentage). On separate charts, it's hard to see how they relate. Merged on a single chart with two different axes, the correlation becomes clear.

• Showing Cause and Effect: Does an increase in ad spend lead to more sales? Plotting marketing budget and revenue on the same timeline can help answer that question at a glance.

• Saving Dashboard Space: If you're building a dashboard, real estate is at a premium. Fusing two or three related charts into one makes your report more compact and easier to digest.

Method 1: The Combination Chart (Best for Different Data Types)

The "Combo" chart is Excel's built-in solution for merging graphs and is the best choice when you want to visualize two different data series that share the same horizontal (category) axis but have different value scales.

Imagine you're a marketing manager tracking monthly website traffic (sessions) and your marketing campaign budget (spend). One is measured in visits, the other in dollars. Combining them shows how your spend impacts traffic patterns.

Step-by-Step Guide to Creating a Combo Chart

1. Prepare Your Data

First, organize your data in a clean table format. The first column should be your shared label (e.g., months, days, categories), and the subsequent columns should contain the numeric data you want to plot.

For our example, the table would look like this:

2. Insert the Chart

Highlight your entire data table, including the headers. Navigate to the Insert tab on the Ribbon, find the Charts section, and click on Recommended Charts. While Excel might suggest a combo chart here, it's often more reliable to create it manually.

Instead, click the tiny icon in the bottom right of the Charts group to open the Insert Chart dialog box. Go to the All Charts tab and select Combo from the list on the left.

3. Configure Your Chart Type and Axes

Now you'll see the Create Combo Chart window. This is where the magic happens. For each of your data series ("Sessions" and "Ad Spend"), you can choose a different chart type.

• Let's keep Sessions as a Clustered Column.

• Change Ad Spend ($) to a Line chart to visually differentiate it.

The problem you'll immediately see is that the "Ad Spend" line is almost flat at the bottom. This is because its scale ($2k-$4k) is tiny compared to the "Sessions" scale (15k-28k). To fix this, you need a secondary axis.

In the same window, next to the "Ad Spend ($)" series, check the box labeled Secondary Axis. Instantly, a new vertical axis appears on the right side of the chart preview, scaled appropriately for your ad spend values. Your line chart will now be perfectly visible against the columns.

Click OK to create the chart.

4. Final Touches

Your combo chart is now created. Take a moment to clean it up for clarity:

• Give the chart a descriptive title, like "Monthly Website Sessions vs. Ad Spend."

• Add axis titles to both the primary and secondary vertical axes. Click the "+" icon next to the chart, check Axis Titles, and then label them "Website Sessions" and "Ad Spend ($)" respectively. This is critical for preventing misinterpretation.

Method 2: Manually Overlaying Two Separate Graphs

Sometimes you may have already created two distinct charts and want to visually place one on top of the other without changing the source data. This method is essentially a graphic design trick within Excel and is useful for presentation purposes.

Step-by-Step Guide to Overlaying Charts

1. Create Your Two Graphs

First, create your two charts as you normally would. For example, create a column chart for sales data and a separate line chart for customer satisfaction scores.

Make sure they both have the same horizontal axis and dimensions for proper alignment.

2. Make the Top Chart Transparent

Decide which chart will be in the foreground (the "top" chart). Usually, a line chart works best on top of a bar or area chart. Click on the Chart Area of this top chart (the empty white space inside its border).

Right-click and select Format Chart Area. A new panel will open on the right side.

• Under the Fill section, select No fill.

• Under the Border section, select No line.

Now, repeat this same process for the Plot Area (the area behind the actual lines or bars). Click inside the gridlines, right-click, select Format Plot Area, and again choose No fill for both the fill and border.

Your top chart now has a completely transparent background.

3. Position and Align the Graphs

Drag the transparent top chart and place it directly over the bottom chart. To perfectly align them, you can use a few tricks:

• Hold the Alt key while dragging and resizing. This will snap the chart's borders to the spreadsheet's cell grid, helping you match their sizes and positions precisely.

• Manually resize the plot areas of both charts so that their axes line up exactly.

4. Group the Charts Together

Once you are happy with the alignment, you'll want to "lock" them together so they move and resize as a single object. Hold down the Shift (or Ctrl) key and click on both charts to select them simultaneously. Right-click on one of the selected charts, go to Group, and select Group again.

Your two separate charts are now grouped into one visual element.

Method 3: Adding a New Data Series to an Existing Chart

Perhaps the simplest way to "merge" graphs is to start with one graph and simply add the data for the second one to it. This works an absolute treat when your data is of a similar type and scale (e.g., comparing sales figures for two different products).

Step-by-Step Guide to Adding a Data Series

1. Have Your Initial Chart Ready

Let's say you already have a line chart showing sales for "Product A" over six months. Elsewhere on your sheet, you have the sales data for "Product B" for the same six months.

2. Use the 'Select Data' Menu

Right-click anywhere on your existing chart and choose Select Data. This brings up the Select Data Source dialog box, showing you the data that's currently powering your chart.

On the left, under Legend Entries (Series), you'll see "Product A." Beneath it, click the Add button.

3. Define the New Series

A small Edit Series window will pop up:

• Series name: Click the cell that contains the header "Product B".

• Series values: Delete the default ={1} content, then click and drag to select the entire range of sales figures for Product B.

Click OK. You’ll now see "Product B" added to the list of series. Click OK again on the main dialog box.

Your chart will instantly update, plotting a new line for Product B right alongside Product A. You've successfully merged the two datasets into a single, easy-to-compare chart.

Final Thoughts

Deciding how to merge graphs in Excel depends on your goal and data structure. For different data scales, combo charts with a secondary axis are the most powerful and professional option. For simple visual consolidation, overlaying and grouping can work well, and for similar data, adding a new series is fast and effective. Mastering these techniques will make your reports more insightful and your dashboards far more efficient.

Manually creating these reports can be time-consuming, especially when your data lives across platforms like Google Analytics, Shopify, or your CRM. At Graphed, we automate this entire process. Instead of struggling with data tables and chart format settings, you can simply ask a question in plain English, like, "Show me a chart comparing last month's ad spend from Facebook with revenue from Shopify." We handle connecting the data and building the visualization instantly, giving you back hours to focus on strategy instead of spreadsheet wrangling.