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Understanding Tableau Data Types

May 22, 2025
4 min read

Updated: May 30, 2025

When it comes to creating insightful and interactive dashboards in Tableau, understanding data types is crucial. Think of data types as the foundation of your data analysis—they determine how Tableau reads, interprets, and visualizes your data. Misunderstanding or misassigning data types can lead to misleading visualizations or calculation errors.

In this blog, we’ll explore the different data types in Tableau, how they work, and why they matter.


Every field (or column) in your dataset has a data type, which tells Tableau what kind of data it is working with.


Tableau:

Tableau is a powerful and widely used data visualization and business intelligence (BI) tool that helps people see and understand their data. It allows users to connect to various data sources, analyze data, and create interactive, shareable dashboards and reports.


Below image shows some sample Online Store Sales DATA

Tableau Data Types

Order ID

Customer

Category

Sales ($)

Profit ($)

Region

101

Alice

Electronics

1,200

300

East

102

Bob

Furniture

250

50

West

103

Carol

Office Supplies

75

20

South

104

Dan

Electronics

800

180

North

105

Emma

Furniture

150

30

East

There are 7 main data types in Tableau


1. Numeric Data Type:

This data type contains numbers like integers or decimal values.

Example in below image OrderID,Sales column and Profit column has Number Values.


Order ID

Sales ($)

Profit ($)

101

1200

300

102

250

50

103

75

20

104

800

180

105

150

30

Usage

  • Numbers are commonly used as Measures in Tableau, where they can be aggregated (summed, averaged, etc.).

  • Numeric fields are often placed on the Axes of visualizations like bar charts, line graphs, or scatter plots.

  • You can perform arithmetic operations like addition, subtraction, or complex statistical calculations using numeric fields as Calculative Field


 2. String Data Type

This data type contains text value. e.g. Name, Labels etc. String can also include digit or symbols.

Example in below image Customer,Category and Region column has string values.


Customer

Category

Region

Alice

Electronics

East

Bob

Furniture

West

Carol

Office Supplies

South

Dan

Electronics

North

Emma

Furniture

East

Usage

  • Strings are typically used as Dimensions, meaning they categorize the data. For example, provider names or visit types can be dimensions in your visualizations.

  • You can Filter visualizations based on string fields, such as filtering by specific types or names.


3. Date Data Type

This data type contains date value for any formate 'DD-MM-YYYY' or 'MM-DD-YYYY'. The date value represents specific time period, which is used for analysis over time, means monitoring changes in days, months or years.

Example in below image, Order Date column has date values

Here is an example showing how the Date Data Type can be used in tabular format:

Order Date

Customer

Category

Region

15-05-2025

Alice

Electronics

East

20-05-2025

Bob

Furniture

West

22-05-2025

Carol

Office Supplies

South

25-05-2025

Dan

Electronics

North

27-05-2025

Emma

Furniture

East

Order Date

15-05-2025

20-05-2025

22-05-2025

25-05-2025

27-05-2025

Date and Time Data Type

An extension of date data type is date and time Data type. A date and time value can be continuous or discrete. It supports all formate of time. There is no time data type in tableau, so comparison will still look at the date component.

Order Date & Time

15-05-2025 09:30 AM

20-05-2025 02:15 PM

22-05-2025 11:45 AM

25-05-2025 04:00 PM

27-05-2025 08:20 AM

Uses

  • Time Series Analysis: Dates are commonly used for time-based analyses, such as tracking sales over time, plotting trends, or analyzing seasonal patterns.

  • Tableau can automatically generate Date Hierarchies (Year, Quarter, Month, Day) to allow you to drill down or roll up across time periods in your analysis.

  • You can create date Filters for specific ranges (e.g., last month, last 30 days, etc.).

  • Calculated Functions like DATEDIFF(), DATEADD(), and DATEPART() allow you to manipulate date fields, calculate differences between dates, or extract specific parts (e.g., year, month).

4. Geographical Data Type

This data type contains geographical field values such as 'Country name', 'Region','City name','Zip code' and 'territories'. Useful to see Geographical map view in tableau.

Example in below  image, City column and State column has geographical data values


City

State

New York

New York

Los Angeles

California

Chicago

Illinois

Houston

Texas

Miami

Florida

Usage

  • Geographic fields allow you to plot data on Maps. For example, if you have country or city names, Tableau can visualize this on a world map or regional map.

  • Tableau has built-in Geocoding to automatically recognize geographic names, but you can also manually assign custom latitude and longitude data if needed.


5. Boolean Data Type

This data type contains numeric values like 'True' or 'False'. Boolean data type is binary data type which has only two type of values '0' or '1'. This data type is useful for categorized data in two distinct outcome.


Customer

Purchase Made

Alice

True

Bob

False

Carol

True

Dan

True

Emma

False

Usage

  • Boolean fields are useful for creating Filters that depend on conditions, such as showing only rows where a condition is TRUE.

  • You can use Boolean fields to control the display of visualizations based on certain conditions (e.g., highlighting rows where profits are negative) is Conditional Formating


6. Cluster Data Type

This data type contains mixed value


Cluster ID

Customers

Avg Sales ($)

Region

High Profit (True/False)

1

Alice, Dan

1,000

East, North

True

2

Bob, Emma

200

West, East

False

3

Carol

75

South

True

7. Null Values

Null values represent missing or undefined data. Tableau highlights these null values so you can either account for or filter them out of your analysis.


Usage

  • Tableau allows you to manage null values in visualizations. You can choose to filter them out, display them separately, or replace them with a default value.

  • Use Null functions like ISNULL() to handle null values in calculations.


Conclusion

For individuals beginning their journey with Tableau, a fundamental understanding of its data types is crucial. Selecting the appropriate data type ensures the accuracy of analyses, minimizes errors, and facilitates efficient adjustments within Tableau.

Overall, Tableau’s data types are intuitive and accessible for most users. Therefore, it can be confidently stated that Tableau data types are easy to comprehend, particularly when one starts with the foundational concepts.

 
 

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