What is Mark Type in Tableau?

Choosing the right chart in Tableau is the first step, but controlling exactly how your data appears within that chart is where the magic happens. This control center is the Marks Card, and at its heart is the concept of a ‘Mark Type,’ the fundamental visual element that represents your data. This guide will walk you through exactly what mark types are, which ones to use, and how to use them to tell a clearer story with your data.

What Are Marks in Tableau?

In Tableau, a "mark" is a visual shape or graphic on a chart that represents one or more rows from your data source. Think of marks as the building blocks of your visualization. If you create a bar chart, each bar is a mark. On a scatter plot, each dot is a mark. On a line chart, each point along the line is a mark. Simple as that.

Every visualization you create in Tableau has a Marks Card, which is the panel (usually located on the left side of your worksheet) where you control the appearance and properties of these marks. You can change their color, size, shape, and most importantly, their type. The Marks Card lets you drag fields onto properties like Color, Size, and Label to manipulate how these marks display information.

Understanding the Different Mark Types in Tableau

The Mark Type dropdown on the Marks Card is where you tell Tableau how you want to represent your data visually. By default, it’s set to ‘Automatic’, meaning Tableau will make an educated guess based on the fields you’re using. For example, if you add a date field and a measure, Tableau often defaults to a line chart. While ‘Automatic’ is useful, true mastery comes from choosing the mark type intentionally.

Let’s explore the most common mark types and when you should use them.

Bar

The humble bar chart is one of the most effective and easily understood visualizations for comparing categorical data. Each bar represents a distinct category, and its length corresponds to a measured value.

• When to Use It: Comparing values across different categories. Examples include total sales by product category, number of support tickets per agent, or marketing spend versus budget for different channels.
• Example: To see your top-selling products, you could place the 'Product Name' dimension on the Rows shelf and the 'Sales' measure on the Columns shelf. Setting the mark type to ‘Bar’ will create a horizontal bar chart that makes it easy to spot the leaders.

Line

Line charts connect discrete data points to show the progression of a value over time, revealing trends, seasonality, or fluctuations.

• When to Use It: Visualizing continuous data, almost always over a time dimension. Think monthly revenue, daily website traffic, or stock prices over a year.
• Example: Place a continuous 'Order Date' field on the Columns shelf and 'Sales' on the Rows shelf. A line mark will instantly show you the sales trend, with peaks and valleys indicating high and low periods.

Area

An area chart is essentially a line chart with the space between the line and the axis filled in with color. This shading helps to emphasize the volume or magnitude of a value over time.

• When to Use It: Showing cumulative totals or volume over a time series. It's excellent for visualizing part-to-whole relationships over time, like tracking market share among a few competitors.
• Example: If you visualized website sessions by channel over the past six months, an area chart could show how the total volume of traffic has changed, while also showing the contribution of each channel within that total (by placing the 'Channel' dimension on the Color property).

Square, Circle, and Shape

These mark types are used to plot individual data points, perfect for scatter plots and symbol maps that show the relationship between two or more measures.

• When to Use It: Identifying correlation, clustering, and outliers. For instance, comparing Sales vs. Profit for different products, or mapping store locations on a map using custom brand logo shapes.
• Circles are often the default for scatter plots.
• Squares provide a slightly different look and can be helpful for creating heat maps.
• Shape: Allows you to use a library of built-in shapes (stars, triangles, plus signs) or even upload your own custom shapes to represent different categories in your data.
• Example: A scatter plot with 'Profit' on Rows and 'Sales' on Columns shows the relationship between the two. Adding 'Product Category' to the Shape property will assign a unique shape for each category, revealing if certain product types are inherently more profitable than others.

Text (Text Table or Crosstab)

Sometimes, the best visualization is no visualization at all - just the numbers. The Text mark type displays your data as text values in a structured table, sometimes known as a cross-tab.

• When to Use It: When precise numbers are more important than the overall trend, or when your audience prefers a tabular view.
• Example: Put 'Region' on Rows and 'Year of Order Date' on Columns, and 'Sales' on the Label property. You'll get a classic cross-tab that breaks down sales by region and year.

Map

When your data contains geographic information (like countries, states or cities), Tableau can automatically plot it on a map. The 'Map' mark type fills in geographic areas (e.g., states) with a solid color, whereas the 'Shape' mark type does it for scatter plots, but in the context of geography.

• When to Use It: Visualizing geographic patterns or comparing values across locations, such as sales by state or population density by country.
• Example: To show the number of customers in each state of the US, you could drag the 'State' field into the view, placing 'Number of Records' on Color, and Tableau would fill in each state with a color corresponding to the number of customers in that state.

Pie

Pie charts get a bad rap in the data visualization community, but they can be effective for a very specific use case: showing part-to-whole relationships or percentages. We're not saying this without caution, use pies cautiously when you have no more than a handful of categories, as it’s hard for them to accurately compare the sizes of slices.

• When to Use It: To show percentage breakdowns where there are only a few categories (like yes/no responses to a survey, or market share).
• Example: Place 'Product Category' on Color, 'Sales' on Angle, and select the 'Pie' mark type from the menu. Tableau will create a pie chart with slices representing the proportions of sales for each category.

Gantt

Gantt charts are specialized visualizations used for mapping project timelines or activity durations. Each mark in a Gantt bar represents a distinct task or event, with its position on the horizontal axis delivering its start and end times.

• When to Use It: Visualizing project schedules, phases, or tracking progress over time.
• Example: Place 'Task Name' on Rows, 'Start Date' on Columns, and add the 'Duration' field to Size. A Gantt mark will create a horizontal bar chart representing the length of each task over time.

How to Change the Mark Type

The process of changing a mark type in Tableau is straightforward:

• Navigate to the Marks card on the left of your worksheet.
• Click on the dropdown menu. It will likely say 'Automatic' by default.
• From the list that appears, select the mark type (Bar, Line, Square, etc.) you want to use for your data.

This action will change the visualization to fit with your new selection.

Moving Beyond Mark Types: Customizing Your Marks

Changing the mark type is only the beginning. The real power of the Marks Card comes from using the other properties - or “shelves” - to encode your data with visual cues. Think of these as adjectives that describe your marks.

• Color: Drag a categorical field (like 'Region') to Color to assign a different color to the marks in each category. Drag a numeric field (like 'Profit') to Color to apply a gradient, making it easy to spot high and low values.
• Size: Drag a numeric field here to control the size of your marks. On a scatter plot of products, you could drag 'Sales' to Size so that products with higher sales appear as larger circles.
• Label: Drag any field to Label to display that information directly on the marks themselves, such as showing the exact sales number on top of each bar.
• Detail: This is a powerful but subtle one. Drag a field to Detail to break down the visualization to a lower level of granularity without changing the chart structure. For instance, on a chart showing total sales per state, adding 'City' to Detail would create a mark for each city within each state without altering the aggregates.
• Tooltip: The tooltip is the box of information that appears when you hover your mouse over a mark. You can customize it by dragging fields to the Tooltip property, adding helpful context without cluttering the main visualization.

Putting It All Together: A Complete Example

Let's create a visual to find out which office supply sub-categories are the most profitable at different sales volumes. The goal is to build a scatter plot from the ground up to showcase how mark types and their properties work together.

1. Set the foundation: Start with an empty worksheet. Drag the 'Sales' measure to the Columns shelf and the 'Profit' measure to the Rows shelf. Tableau will initially create a single mark at the intersection of total sales and total profit.
2. Increase the Level of Detail: We don't want to see just one mark, we want to see a mark for each of our product sub-categories. Drag the 'Sub-Category' dimension from the Data pane and drop it onto the Detail property on the Marks card. Your view will instantly explode into multiple marks - one for each sub-category.
3. Choose the Mark Type: Tableau likely defaulted to a 'Circle' or 'Shape' mark, which is perfect for a scatter plot. For clarity, click the Mark Type dropdown and explicitly select Circle. Now, each circle represents a specific product sub-category, positioned by its total sales and profit.
4. Add Color for Insight: How do we quickly see which sub-categories are losing money? Drag the 'Profit' measure and drop it on the Color property. Tableau assigns a color gradient, making it immediately obvious which points are profitable (e.g., blue) versus unprofitable (e.g., orange/red).
5. Encode Data with Size: Which sub-categories are our biggest sellers? Drag the 'Sales' measure and drop it on the Size property. The circles will now change in size, with larger circles representing higher sales volumes. You can now see high-sale/high-profit items as large, dark blue circles.
6. Label the Data: For easier identification, drag the 'Sub-Category' dimension one more time and drop it on the Label property. This will place the name of each sub-category next to its corresponding circle, removing the need to rely only on the tooltip.

In just a few steps, you've gone from a single data point to a rich visualization. You have bars sized by sales, colored by profitability, and labeled for clarity, making it easy to draw actionable insights - all by manipulating marks.

Final Thoughts

Mastering mark types and the Marks Card is your key to unlocking Tableau's expressive power. By moving beyond the 'Automatic' setting, you can intentionally choose the best visual representation for your data, then layer on more information with color, size, and labels to tell a compelling and insightful story.

Learning the nuances of tools like Tableau, from mark types to data joins, is a powerful skill but requires a significant time investment. We built Graphed to remove that complexity entirely. By connecting your marketing and sales data sources, you can create real-time dashboards and get answers just by asking questions in plain English - no need to drag pills, configure Marks Cards, or manage settings. It's the same deep analytical power, unlocked in seconds instead of hours.