How to Add Background Image in Tableau Worksheet

Adding a background image to your Tableau worksheet is a fantastic way to give your data powerful context, turning a standard chart into a rich, custom map or diagram. This guide will walk you through the entire process, from preparing your data and image to troubleshooting common issues and applying best practices.

Why Use a Background Image in Tableau?

While Tableau's built-in map layers are excellent, some analyses require a more specific or custom visual context. Instead of just plotting latitude and longitude on a world map, background images allow you to map data onto virtually any visual you can imagine.

This moves your dashboards from being purely informational to deeply contextual. Here are a few examples to get you thinking:

• Retail and Operations: Visualize shopper traffic, sensor data, or inventory placement on a store floor plan.
• Live Events: Map ticket sales, entry gate traffic, or social media mentions onto a stadium or festival layout.
• Manufacturing: Track production stages, equipment failures, or quality control checks on a factory floor schematic.
• Healthcare: Plot patient data or medical findings onto an anatomical diagram or medical scan.
• Real Estate: Show available units, pricing, or occupancy rates within a building's floor plan.

In all these cases, the background image provides an intuitive reference frame that makes the data instantly understandable to anyone who sees it, even those completely unfamiliar with the underlying numbers.

Before You Begin: Preparing Your Image and Data

Flawless execution in Tableau starts with good preparation. Before you even open a new worksheet, you need two things correctly configured: your image and your data. Investing a few minutes here will save you a ton of frustration later.

1. Prepare Your Background Image

First, choose the image you want to use. This could be anything from a blueprint or seating chart to a product diagram. For best results, keep these tips in mind:

• Keep it Simple: Busy or dark images can obscure your data points. A simple line drawing or a map with muted colors works best. If your image is noisy, you can use Tableau's "washout" feature to fade it into the background.
• Optimize the File Size: Large, high-resolution images can dramatically slow down your dashboard's loading time. Resize and compress your image to be as small as you can while still maintaining clarity. A width of 1,000 to 2,000 pixels is usually sufficient.
• Know Your Dimensions: You need to know the exact pixel dimensions (width and height) of your image. You can easily find this on a Mac by right-clicking the file and selecting "Get Info," or on Windows by right-clicking, choosing "Properties," and looking under the "Details" tab. For example, your image might be 1280 pixels wide by 720 pixels tall. Jot this down, you will need it inside Tableau.

2. Prepare Your Data with Coordinates

This is the most critical part of the process. For Tableau to know where on your image to plot a data point, your data must contain specific X and Y coordinates that correspond to that image.

Each row in your dataset needs a column for the X-axis position and a column for the Y-axis position. Think of your image as a classic grid from math class: the X-axis runs horizontally and the Y-axis runs vertically.

For example, let’s say we want to plot the location of department hot-desks on an office floor plan. Our data might look like this:

Desk_ID, Department, Occupancy_Status, X_Coordinate, Y_Coordinate 101, Marketing, Occupied, 150, 600 102, Marketing, Available, 175, 600 201, Sales, Occupied, 450, 320 202, Sales, Occupied, 475, 320 301, Engineering, Available, 980, 450

How Do I Get Coordinates from My Image?

If you don’t have coordinates, you’ll need to generate them. The method is straightforward but requires some manual effort:

1. Open your image in a simple image editor like Preview on Mac, Paint on Windows, or any online tool.
2. Most image editors display the pixel (px) coordinates of your cursor as you move it around the canvas, often in the bottom status bar.
3. Move your cursor to the location you want to plot data and record the X and Y pixel values in your spreadsheet.
4. Your coordinate system starts at the top-left corner:

Once your dataset has these XY columns for every data point, you’re ready to head into Tableau.

Step-by-Step Guide to Adding Your Background Image

With an image ready and data prepared, it's time to build your visualization.

Step 1: Connect to Your Data

Open Tableau and connect to the data source you prepared (e.g., your Excel or CSV file containing the X and Y coordinate columns).

Once loaded, head to a new worksheet. In the Data pane on the left, you should see your fields, including "X_Coordinate" and "Y_Coordinate." It is essential to ensure Tableau recognizes these as Measures. By default, they should appear as continuous measures (green pills). If they appear as discrete dimensions (blue pills), right-click on each and select "Convert to Continuous."

Step 2: Add Your Fields to the Canvas

Drag your X-coordinate field to the Columns Shelf and your Y-coordinate field to the Rows Shelf. This creates an empty scatter plot. This is the blank canvas for your custom map.

Step 3: Open the Background Image Menu

From the top menu bar, navigate to Map > Background Images and select your current data source. This will open the Background Images dialog box. This is where you configure all of your settings.

Step 4: Configure Your Background Image

In the Background Images dialog box, click the Add Image… button. This will open the Add Background Image configuration window. This is where you connect the dots between your image, your coordinates, and your canvas.

This window has several important fields you must configure correctly:

1. Browse for Your Image: Click the "Browse..." button and locate the image file on your computer.
2. Map X Field to Your Image Width:
3. Map Y Field to Your Image Height:
4. Adjust the Washout: This slider makes your image more transparent. Dragging it to the right fades the image, which helps your data points, text, and colors stand out. A starting point of around 50-70% works well.

Click OK twice to close both dialog boxes. And just like that, you should see your background image appear in your worksheet with your data points plotted on top!

Step 5: Refine and Enhance Your Visualization

Now that the image is in place, you can treat your visualization like any other Tableau chart. Here are some ideas:

• Drag the Occupancy_Status field to the Color shelf on the Marks card to see which employee desks are available vs. occupied.
• Change the mark type from a default shape to a circle and drag the Department field to the Shape shelf for an extra layer of analysis.
• Add Desk_ID and Department to the Tooltip so users can hover over a point for more details.

Common Issues and Troubleshooting Tips

Sometimes, things don't look quite right on the first try. Here’s a checklist for fixing the most common issues:

"My Image Isn't Showing Up at All!"

• Double-check that you added your X and Y coordinate fields to the Columns and Rows shelves correctly.
• Go back to Map > Background Images, select your image, and click "Edit." Make sure all the bounds you typed are correct and that the "Enabled" checkbox at the bottom is checked.
• If one of your axes is reversed, your entire canvas might have a negative scale, and it will just be a blank page if that happens. Make changes in their axis settings.

"All My Data is Clumped in a Corner."

• This is almost always an issue with the axis bounds. Your data coordinates are likely on a much smaller scale than your axes dimensions. Ensure that your X and Y-coordinate inputs in the image-options dialog boxes are correct relative to your data scale and image dimensions.
• If your data coordinates and image dimensions are vastly different, you may need to rescale one of them in your original data source or image editor.

"My Image is Stretched or Looks Distorted."

• Re-open the "Edit Image" dialog. Under the "Options" tab, make sure that Lock Aspect Ratio is checked. This forces the image to maintain its original proportions. Also, consider setting your workbook view to 'Normal' or 'Fit Height' rather than 'Fit to Width,' because sometimes this can stretch your images.
• Another pro tip is to "Fix" your axis to their exact range to lock it on view. To do this, right-click on the X-axis and select "Edit Axis." Select Fixed, start at zero, and 'Fixed' end to be your maximum value of the coordinates, for both the X and Y axes. It will keep the correct aspect ratio whenever you resize the chart.

Final Thoughts

Mapping data onto custom coordinates provides much better insights as the dashboard's view is far better than default geographic maps available in Tableau. With correct preparations of the image coordinate system, adding any appropriate background is a straightforward process according to the specific context under your analysis.

While Tableau gives you deep control over these customizations, it also takes considerable effort to have your visualizations prepared beforehand, which can delay you. At Graphed, we automate most common sales and marketing tasks through a drag-and-drop builder with just a few lines typed into plain English, thus eliminating complex configuration menus. If getting fast and accurate reports on your e-commerce campaigns is all that matters to you, we are here for that purpose only. No data manipulation! Just plain English and instant answers.