What is Ads.txt?

Ads.txt, (Authorized Digital Sellers), is an initiative launched by the Interactive Advertising Bureau (IAB) to increase transparency in the programmatic advertising ecosystem.

Essentially, it is a text file that publishers host on their domain, which lists the specific ad sources that are authorized to sell their ad inventory. 


Why is Ads.txt useful?

Ads.txt helps solve the rapidly growing problem of fraudulent inventory in websites, which prompts advertising buyers to waste huge sums of money; website owners lose legitimate revenue for their unique content. For more information on this issue and statistics of the world and the Baltic States click here.


How does Ads.txt work?

The basic principle of Ads.txt is very similar to that of robots.txt: the information is presented in a plain text, separated by commas; each entry is made on a new line. The file is placed on a particular website by its owner; it contains the list of companies that can sell the entire inventory on the site.


Where to find Ads.txt on a website?

This file is placed in the website’s /root folder and is accessible directly, i.e.


How do I create Ads.txt?

There is a plethora of automated platforms that may help you create your ads.txt file, starting from proprietary Google tools and ending with a stack of independent 3rd party solutions, however be sure to add all relevant entries gathered from all of your partners. On the other hand, Ads.txt file can be easily created with Notepad or any other text editor. According to IAB specifications, these fields, separated by a comma, in the file are mandatory:

Advertising systems, SSP or RTB platform domain (e.g.

Unique website’s account ID in the system (e.g., 12345);

Type of account/cooperation type (DIRECT or RESELLER);

Each different system and information related is given on a new line.

Example: The website places Ads.txt file on its server, where states that its traffic could be sold by three advertising systems and gives its account ID on the following systems:, 12345, DIRECT, pub-1257, DIRECT, ca-975841, RESELLER


What is the difference between DIRECT and RESELLER

If you have a direct contact with a monetization partner (e.g. “Google”) and administer the account yourself, in this case, your cooperation with “Google” is DIRECT.

If site’s traffic is sold by resellers, then these sellers specify in which platforms it is possible to buy your traffic, as well resellers’ ID on those platforms and their role, i.e. RESELLER.


Where to get the information needed for Ads.txt?

This information is most commonly available on each platform’s account. The easiest way is to ask for this information from your site inventory monetization partner.


What if I work with several advertising partners/networks/exchanges/SSP’s?

In this case, you must provide information about all the partners in separate lines in the Ads.txt file. Ask for this information from your partners and merge everything into one Ads.txt file according to the specified template given above.


Have any additional questions?

Drop us a letter at gediminas.blazys [at] digitalmatter [dot] ai

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