DOMAIN Function

Finds the value for the domain from a valid URL. Input values must be of URL or String type.In this implementation, a domain value is all data between 1) the protocol identifier (if present) and the sub-domain and 2) the trailing, top-level domain information (e.g. .com).

NOTE: When the DOMAIN function parses a multi-tiered top-level domain such as, the output is the first part of the domain value (e.g. co).

Basic Usage

URL literal examples:

derive value: DOMAIN('' ) as: 'myDomain'

Output: Generates a column containing the value example.

derive value: DOMAIN('' ) as: 'myDomain'

Output: Generates a column containing the value e.

Column reference example:

derive value: DOMAIN(myURLs) as: 'myDomain'

Output: Generates the new myDomain column containing the domain values extracted from the myURLs column.


derive value: DOMAIN(column_url)

ArgumentRequired?Data TypeDescription
column_urlYstringName of column or String or URL literal containing the domain value to extract

For more information on syntax standards, see Language Documentation Syntax Notes.


Name of the column or URL or String literal whose values are used to extract the domain value.

  • Missing input values generate missing results.
  • Multiple columns and wildcards are not supported.

Usage Notes:

Required?Data TypeExample Value
YesString literal or column reference (URL)


Example - Filter out internal users

Here is some example web visitor information, including the name of the individual and the referring URL. You would like to filter out the internal users, whose referrer values include test-value.

Joe Guy
Ian Holmes
Nick Knight
Axel Adams
Teri Towns


The referrrer values include test-value as a non-domain value and varying URLs from the domain. So, you should use the DOMAIN function to parse only the domain versions of these values. The following evaluates the Referrer column values for the test-value domain and generates true/false answers in a new column accordingly:

derive value:IF(DOMAIN(Referrer)=='test-value',true,false) as:'isInternal'

Now that these values are flagged, you can filter out the internal names:

delete row:(isInternal == 'true')


Joe Guyhttp://www.example.comfalse
Axel Adamshttp://www.example.comfalse
Teri Towns

Example - Domain, Subdomain, and Suffix functions

This examples illustrates how you can extract component parts of a URL using the following functions:

  • DOMAIN - extracts the domain value from a URL. See DOMAIN Function.
  • SUBDOMAIN - extracts the first group after the protocol identifier and before the domain value. See SUBDOMAIN Function.
  • SUFFIX - extracts the suffix of a URL. See SUFFIX Function.


Your dataset includes the following values for URLs:



When the above data is imported into the application, the column is recognized as a URL. All values are registered as valid, even the IPv4 address.

To extract the domain and subdomain values:

derive value: DOMAIN(URL) as: 'domain_URL'

derive value: SUBDOMAIN(URL) as:'subdomain_URL'

derive value: SUFFIX(URL) as:'suffix_URL'

You can use the Cloud Dataprep pattern in the following transform to extract protocol identifiers, if present, into a new column:

extract col:URL on:`{start}%*://`

To clean this up, you might want to rename the column to protocol_URL.

To extract the path values, you can use the following regular expression:

NOTE: Regular expressions are considered a developer-level method for pattern matching. Please use them with caution. See Text Matching.

extract col: URL on: /[^*:\/\/]\/.*$/

The above transform grabs a little too much of the URL. If you rename the column to path_URL, you can use the following regular expression to clean it up:

extract col:path_URL on:/[!^\/].*$/

If you drop the path_URL column and rename the path_URL1 column to the dropped one, you should have the following results:


URLpath_URLprotocol_URLsubdomain_URLdomain_URLsuffix_URL wwwexamplecom examplecom http:// www.appexamplecom www.some.appexamplecom some.appexamplecom someexamplecom examplecom

Send feedback about...

Google Cloud Dataprep Documentation