Area charts in Tableau - Step-by-Step Guide

Introduction

Area charts show how values change over time or categories by filling the space below a line. They help you see trends and compare parts of a whole in a simple visual way.

When you want to show sales growth over months with a clear visual of total volume.

When comparing website traffic sources over weeks to see which source contributes most.

When displaying budget spending over quarters to highlight cumulative amounts.

When illustrating population changes by age groups to show distribution.

When you want to emphasize the size of different categories over time.

Steps

Step 1: Open your Tableau workbook

- Tableau Desktop start screen or existing workbook

Your data source and sheets are visible

💡 Make sure your data has a date or category field for the x-axis

Step 2: Drag the date or category field to the Columns shelf

- Columns shelf at the top of the worksheet

The horizontal axis shows your time or categories

Step 3: Drag the measure you want to visualize to the Rows shelf

- Rows shelf next to Columns shelf

A line chart appears showing the measure over time or categories

Step 4: Click the Show Me panel on the right

- Show Me panel in Tableau interface

Chart type options appear

💡 If Show Me is not visible, click the Show Me button on the toolbar

Step 5: Select the Area chart icon in the Show Me panel

- Show Me panel area chart icon (looks like a filled line chart)

The line chart changes to an area chart filling the space below the line

Step 6: Adjust colors or add labels if needed

- Marks card and Labels shelf

The area chart updates with your custom colors or labels

Before vs After

Before

A line chart showing sales over 12 months with a simple line and no fill

After

An area chart showing sales over 12 months with the area below the line filled in blue

Settings Reference

Mark Type

📍 Marks card

Controls the visual style of the chart; set to Area for area charts

Default: Automatic

Color

📍 Marks card > Color

Sets the fill color of the area to improve visual appeal or show categories

Default: Single color

Label

📍 Marks card > Label

Displays data values on the chart for clarity

Default: Hide labels

Stack Marks

📍 Analysis menu > Stack Marks

Controls whether multiple area series stack on top of each other or overlap

Default: On

Common Mistakes

Choosing the wrong field for the Columns shelf, such as a measure instead of a date or category

Area charts need a continuous or discrete category on the x-axis to show progression or groups

Always use a date or categorical field on Columns to define the horizontal axis

Not switching the mark type to Area and leaving it as Line

The chart will not fill the area below the line, missing the main visual effect

Use the Show Me panel or Marks card to set the mark type to Area

Stack Marks turned off when multiple categories are present

Areas may overlap confusingly instead of stacking clearly

Turn on Stack Marks from the Analysis menu to stack areas properly

Summary

Area charts fill the space below a line to show volume and trends clearly.

Use a date or category field on the x-axis and a measure on the y-axis.

Set the mark type to Area and adjust stacking for multiple series.

Practice

1. What is the main purpose of an area chart in Tableau?

easy

A. To show trends and the total amount by filling the area under a line

B. To display individual data points without connecting lines

C. To compare categories using bars of different lengths

D. To show relationships between two numerical variables using dots

Solution

1. Step 1: Understand area chart basics

   An area chart fills the space under a line to emphasize the magnitude of values over time or categories.

2. Step 2: Compare with other chart types

   Unlike scatter plots or bar charts, area charts focus on trends and totals by shading the area below the line.

3. Final Answer:

   To show trends and the total amount by filling the area under a line -> Option A

4. Quick Check:

   Area chart = filled trend line [OK]

Hint: Area charts fill space under lines to show totals [OK]

Common Mistakes:

• Confusing area charts with scatter plots
• Thinking area charts only show individual points
• Using area charts to compare unrelated categories

2. Which of the following is the correct way to create an area chart in Tableau?

easy

A. Drag a measure to Filters, a dimension to Pages, then select 'Line' mark type

B. Drag a dimension to Rows, a measure to Columns, then select 'Circle' mark type

C. Drag two measures to Rows and Columns, then select 'Bar' mark type

D. Drag a measure to Rows, a dimension to Columns, then select 'Area' mark type

Solution

1. Step 1: Identify correct field placement

   For area charts, a measure (numeric data) goes on Rows and a dimension (categories or time) on Columns.

2. Step 2: Choose the correct mark type

   After placing fields, select the 'Area' mark type to fill the area under the line.

3. Final Answer:

   Drag a measure to Rows, a dimension to Columns, then select 'Area' mark type -> Option D

4. Quick Check:

   Measure + Dimension + Area mark = Area chart [OK]

Hint: Measure on Rows + Dimension on Columns + Area mark [OK]

Common Mistakes:

• Using Circle or Bar mark types instead of Area
• Placing dimensions on Rows instead of Columns
• Not selecting the Area mark type after placing fields

3. Given a dataset with sales over months and product categories, what will happen if you create an area chart with Month on Columns, SUM(Sales) on Rows, and Category on Color?

medium

A. The chart will show stacked colored areas for each category over months

B. The chart will show separate lines without filled areas

C. The chart will show a single color area for total sales only

D. The chart will produce an error because color cannot be used here

Solution

1. Step 1: Understand field roles in area chart

   Month on Columns creates the timeline, SUM(Sales) on Rows shows total sales, and Category on Color splits the area by product categories.

2. Step 2: Visualize the result

   Each category's sales area stacks on top of others, showing contribution per month with different colors.

3. Final Answer:

   The chart will show stacked colored areas for each category over months -> Option A

4. Quick Check:

   Color by category = stacked colored areas [OK]

Hint: Color splits area into stacked parts by group [OK]

Common Mistakes:

• Expecting separate lines instead of stacked areas
• Thinking color only changes line color, not area
• Assuming color cannot be used with area charts

4. You created an area chart but the areas overlap and colors are not stacked. What is the most likely cause?

medium

A. The color field is missing or not assigned

B. The dimension is on Rows instead of Columns

C. The mark type is set to 'Line' instead of 'Area'

D. The measure is aggregated incorrectly

Solution

1. Step 1: Check the mark type

   If the mark type is 'Line', the chart shows lines without filled areas, causing overlap and no stacking.

2. Step 2: Confirm correct mark type for area chart

   Changing the mark type to 'Area' fills the space under the lines and stacks colors properly.

3. Final Answer:

   The mark type is set to 'Line' instead of 'Area' -> Option C

4. Quick Check:

   Line mark = no filled areas [OK]

Hint: Use 'Area' mark type to avoid overlapping lines [OK]

Common Mistakes:

• Ignoring mark type and blaming data placement
• Not assigning color field for stacking
• Misunderstanding aggregation effects on area charts

5. You want to compare monthly sales trends for two regions using an area chart in Tableau. Which approach best highlights differences clearly?

hard

A. Place Region on Columns, Month on Rows, and SUM(Sales) on Size with 'Circle' mark type

B. Place Month on Columns, SUM(Sales) on Rows, and Region on Color with 'Area' mark type

C. Place Month on Rows, Region on Columns, and SUM(Sales) on Rows with 'Bar' mark type

D. Place SUM(Sales) on Columns, Month on Rows, and Region on Detail with 'Line' mark type

Solution

1. Step 1: Set timeline and measure correctly

   Month on Columns creates the timeline axis, SUM(Sales) on Rows shows sales values.

2. Step 2: Use Region on Color with Area mark

   Assigning Region to Color splits the area chart into colored stacked or overlapping areas per region, making differences visible.

3. Final Answer:

   Place Month on Columns, SUM(Sales) on Rows, and Region on Color with 'Area' mark type -> Option B

4. Quick Check:

   Color by region + Area mark = clear comparison [OK]

Hint: Use color for groups and area mark for trends [OK]

Common Mistakes:

• Using Circle or Bar marks instead of Area
• Placing Region on Columns instead of Color
• Not using Month on Columns for timeline