How to Create Two Charts in One Sheet in Tableau

Putting two different charts into a single view in Tableau is one of the most practical skills you can learn. Instead of showing sales on one chart and profits on another, you can layer them together to instantly see how they relate. This guide will walk you through the two primary methods for combining charts in one sheet: the combined axis chart and the dual axis chart.

Why Combine Two Charts in One Sheet?

Before we jump into the "how," let's quickly cover the "why." Combining charts isn't just a neat trick, it serves a real purpose in data visualization.

Direct Comparison: The most obvious benefit is the ability to directly compare two or more metrics. Seeing sales trends plotted alongside profit trends on the same timeline instantly reveals their relationship. Are they moving together, or does one lag behind the other?
Saves Dashboard Space: Every pixel on a dashboard is valuable real estate. Combining related metrics into a single chart frees up space, preventing your dashboards from feeling cluttered and overwhelming.
Reveals Correlations: Layering different data points - like marketing spend and website traffic, or units sold and customer returns - can highlight correlations you might otherwise miss. It's much easier to spot these connections when the data is seen in a unified context.
Tells a Richer Story: A chart showing only website traffic is good. A chart showing both traffic and conversion rate tells a much more compelling story about how effective that traffic is at generating results.

In short, it adds context. You move from showing isolated numbers to showing the relationships between them, which is the foundation of powerful data analysis.

First, A Quick Refresher: Dimensions vs. Measures

To build anything in Tableau, you need to understand the fundamental difference between Dimensions and Measures. This distinction is especially important when combining charts.

Dimensions: These are your categorical, qualitative fields. They are the things you use to slice and dice your data. Think of them as the "who, what, where, and when" of your dataset. Examples include Customer Name, Product Category, Region, and Order Date. When you drag a dimension to a view, you are adding more detail or context.
Measures: These are your numerical, quantitative fields - the numbers you can perform mathematical calculations on (sum, average, count, etc.). Examples include Sales, Profit, and Quantity. When you drag a measure to a view, Tableau automatically aggregates it (usually as a SUM).

You can tell them apart in the Tableau side pane: dimensions are typically blue, and measures are green. Understanding this will help you know exactly which pills to drag where.

Method 1: Creating a Combined Axis Chart

A combined axis chart brings two or more measures together to share a single axis. This method is ideal when your measures share the same unit and have a similar scale.

When to use it: Comparing Sales vs. Profit (both in dollars), Actual Revenue vs. Target Revenue, or number of New Customers vs. Returning Customers.

When to avoid it: Comparing Sales (in the millions of dollars) with Quantity Sold (in the hundreds). The massive difference in scale will flatten the "Quantity" line, making it unreadable.

Step-by-Step Guide to a Combined Axis Chart

We'll use the Sample - Superstore data in Tableau. Let’s create a chart that shows Sales and Profit over time.

Set up the basic chart: Drag the dimension Order Date to the Columns shelf. Right-click the Order Date pill and choose the continuous "Month" option (the one with the calendar and year). This will give you a continuous timeline.
Add the first measure: Drag the measure Sales to the Rows shelf. You will now have a basic line chart showing sales over time.
Combine the second measure: Now, drag the Profit measure from the side pane and drop it directly onto the existing Sales axis in your chart. As you hover over the axis, Tableau will show a subtle visual cue - often a faint ruler icon. When you see it, release the mouse button.
Review the result: Tableau automatically combines the two. You now have two line charts on a single axis. Notice in your shelves that the SUM(Sales) pill has been replaced by a Measure Values pill. In the Marks card, a Measure Names pill has appeared, automatically assigned to the Color property, which gives each line a distinct color. Your legend updates accordingly.

That’s it! You’ve successfully created a combined axis chart. You can now format the lines, colors, and tooltips just like any other chart to make your visualization clear and easy to read.

Method 2: Building a Dual Axis Chart

A dual axis chart overlays two separate charts on top of each other, each with its own independent axis. This is perfect for comparing two measures with completely different scales or units.

When to use it: Comparing Sales (in dollars) with Quantity Sold (a count), or Website Sessions vs. Conversion Rate (a percentage).

Step-by-Step Guide to a Dual Axis Chart

Let's create a chart showing Sales revenue alongside the Quantity of items sold.

Create your first chart: Just like before, start by dragging Order Date to Columns (set to continuous Month) and Sales to Rows.
Add the second measure without combining: Drag your second measure, Quantity, to the Rows shelf and place it to the right of the SUM(Sales) pill. This will create two separate line charts, stacked one on top of the other, in the same sheet.
Create the Dual Axis: Right-click the second measure pill (SUM(Quantity)) on the Rows shelf and select Dual Axis from the dropdown menu.
Review and format: Tableau combines the charts, creating a second axis for Quantity on the right side. You’ll also notice that your Marks card has now been split into three tabs: All, SUM(Sales), and SUM(Quantity). This is the key benefit - it lets you control each chart's appearance independently. For example, you can click on the SUM(Sales) marks card and keep it as a line chart, then click on the SUM(Quantity) card and change its mark type to bars.

An Essential Step: Synchronizing Axes (When Necessary)

When you create a dual axis chart with two measures that share the same unit (like Sales and Profit), the axes might have different scales by default, which can be misleading. Always right-click the secondary axis (the one on the right) and select Synchronize Axis. This locks the scales together, ensuring an accurate visual comparison. If your measures have different units (like dollars and a count), you do not need to synchronize them.

Best Practices for Combined Charts

Keep It Simple: While you can combine more than two measures, it's rarely a good idea. Three or more lines on one chart can quickly become a tangled mess. Stick to two for clarity.
Use Color and Shape Effectively: Use distinct and accessible colors to differentiate your measures. With dual axis charts, you can also use different shapes or mark types (like a line for one and bars for the other) for even better visual separation.
Clear Labeling is Non-Negotiable: Make sure both axes are clearly labeled with the measure name and unit. A descriptive title and informative tooltips go a long way in helping your audience understand the chart at a glance.
Know when to use which method. A quick recap of what we’ve discussed:
- Combined-Axis Chart: Use for comparing similar measures on the same scale. It compares values side-by-side using one shared axis.
- Dual-Axis Chart: Use for comparing measures of different types or on different scales. It combines mark types and provides two independent axes for contextual comparisons of magnitude and trend.

Final Thoughts

Mastering combined and dual axis charts is a huge step forward in your Tableau journey. It allows you to create dense, information-rich visuals that reveal connections in your data far better than separate charts ever could. By choosing the right method - combined axis for similar scales and dual axis for different ones - you can build professional, insightful dashboards.

While Tableau is a powerful tool for this kind of work, there is a learning curve to creating custom analyses. Even a seemingly simple task like building a dual-axis chart requires several clicks, drags, and formatting adjustments. Often, marketers and business owners just want a straightforward answer without becoming a dashboard expert. Here at Graphed, we've designed our platform so you get insights by simply asking a question in plain English. No more dragging pills or configuring axes. Just describe the chart you need - "compare sales and quantity sold as a dual axis chart for last year" - and our AI builds an interactive, real-time dashboard for you in seconds.