Looker Studio Function : CONCAT

Category: Text Function

The CONCAT function in Looker Studio is a commonly used text function that helps in combining two or more text values into a single string. In real-world dashboards, data usually comes from different columns — for example, first name and last name, city and state, product code and SKU, or year and month. Instead of showing these values separately, CONCAT allows us to merge them into one meaningful field.

From my experience working on sales and marketing dashboards, CONCAT becomes very useful when preparing readable labels, custom IDs, or formatted text for reports shared with management. It is especially helpful when data sources do not provide pre-formatted text fields and we need to create them inside Looker Studio itself.

The function works only with text values, so numbers and dates must be converted into text before using CONCAT. When used correctly, it improves dashboard clarity and avoids unnecessary data preprocessing in the source.

Overall, CONCAT is a simple but powerful function that every Looker Studio user should understand, especially when dealing with dynamic labels and calculated dimensions.

Purpose of the CONCAT Function

1. Combine Multiple Text Fields

CONCAT is mainly used to merge two or more text columns into one readable output, such as combining first name and last name.

2. Create Custom Labels

It helps in creating meaningful labels like “Order-2025-001” by joining static text with dynamic values.

3. Improve Dashboard Readability

Instead of showing multiple columns, CONCAT allows clean and compact text fields for charts and tables.

4. Generate Unique Text Identifiers

By combining fields like date, region, and product, we can generate custom IDs for reporting purposes.

Type of Calculation & Practical Use Cases

1. Calculated Dimension

CONCAT is generally used as a calculated dimension, not a metric.

2. Dynamic Field Creation

Useful when the data source does not contain a combined text field but reporting requires it.

3. Reporting & Visualization

Helps create better titles, labels, and legends inside charts and scorecards.

4. Data Formatting

Used to format raw data into business-friendly text without changing the source data.


CONCAT(text_expression1, text_expression2)

CONCAT Function – Parameters Table

ParameterTypeDescription
text_expression1TextFirst text value or field
text_expression2TextSecond text value or field to join

How Does the CONCAT Function Work?

The CONCAT function takes two text expressions and joins them exactly in the order provided. It does not automatically add spaces or separators. If spacing or symbols are required, they must be added manually as text values.

For example, if you want a space between two fields, you must include " " as one of the parameters. CONCAT processes row-level data, meaning it works independently for each record in the dataset.

If any parameter is NULL, the function may return an empty or unexpected result, so handling null values is recommended for clean output.

When Should You Use CONCAT Function?

  1. When you need to merge two text fields into one

  2. When creating user-friendly labels for dashboards

  3. When building formatted IDs or reference numbers

  4. When source data lacks combined text fields

  5. When you want to avoid modifying the original data source

Examples of CONCAT Function

Example 1: Combine First Name and Last Name
CONCAT(First_Name, Last_Name)

Output: RahulSharma

👉 To add space:

CONCAT(First_Name, " ", Last_Name)

Example 2: Create Order Label
CONCAT("Order-", Order_ID)

Output: Order-1025


Example 3: Combine City and State
CONCAT(City, ", ", State)

Output: Mumbai, Maharashtra


Tips & Best Practices

  • Always add spaces or separators manually

  • Convert numbers or dates to text before concatenation

  • Avoid too many nested CONCATs — keep it readable

  • Handle NULL values to avoid blank results

  • Use CONCAT mainly in dimensions, not metrics

1. Can CONCAT combine more than two values?

Yes, but you need to nest multiple CONCAT functions.

2. Does CONCAT work with numbers?

No. Numbers must be converted to text before using CONCAT.

3. Is CONCAT a metric or dimension function?

It is mainly used as a calculated dimension.

4. Does CONCAT add spaces automatically?

No. Spaces or symbols must be added manually.

5. What happens if one value is NULL?

The result may be blank. It’s better to handle NULLs explicitly.