Tags API

BuiltWith Tags API

Related domains to IPs and other site attributes


Get XML and JSON results of websites that are using specific IP addresses, Google Analytics Tags and more.

The general access method is as follows -
https://api.builtwith.com/tag1/api.[xml|json]?KEY=[YOUR KEY]&LOOKUP=[ATTRIBUTE-TYPE]-[CODE]


You must provide your API key in each lookup. See the examples for how this works.

Login or Create a Free Account to get your API key.

Get Tag Example

XML Get Single Domain
https://api.builtwith.com/tag1/api.xml?KEY=[YOUR KEY]&LOOKUP=IP-

JSON Get Single Domain
https://api.builtwith.com/tag1/api.json?KEY=[YOUR KEY]&LOOKUP=CA-PUB-1894893914772263



The following GET parameters can be supplied for lookups

Name Examples Required
KEY 00000000-0000-0000-0000-000000000000
Sign up for Free or Login to get a key.
Attributes that you'd like to lookup - the list of attribute types is available at https://api.builtwith.com/tag1/api.xml?TYPES=true (json)

Multi-Lookup Option
You can lookup 16 attributes at a time - seperate them with a comma. For example IP-,CA-PUB-1894893914772263 - this dramatically improves throughput.


The Tags API will respond with a document in the format -


Identifier is the sub-option in the identifers array.

Name Example Description
Value IP- The tag that was looked up.
Identifers Identifier explained below Explained below

Matches are other domains that have this identifier.

Name Example Description
Domain tjoos.com The domain name of the match
First 2013-03-26T13:00:00Z The date we first detected this tag
Last 2016-04-23T14:00:00Z The date we last detected this tag

Code Examples

JSON/XML have integrations in all modern programming languages. Here's some StackOverflow topics for various languages - Python, C#, Java, PHP, C++, TSQL and Ruby.

Error Codes

Note error messages in this format cannot be guaranteed, your implementation should also consider non-200 response codes as errors. The Lookup property will be null (json) or not provided (xml) if the error is server related. View all potential well-formed error codes.

Terms of Use

Our standard terms cover the use all of our APIs.

In general, you can use the API to enhance your product in many ways. The only limitation is you cannot resell the data as-is or provide duplicate functionality to builtwith.com and its associated services.