ads.txt file

ads.txt file: A Tool for Digital Ad Inventory

ads.txt file means Authorized Digital Sellers. It is an initiative of IAB(Interactive Marketing Bureau Tech Laboratory) & helps make sure that your digital advertising inventory is sold through sellers (eg, It means who you’ve recognized /authorized. Creating your personal ads txt offers you more control & contains a list of sellers who are permitted to sell advertisements on your own site. It aids in preventing counterfeit inventory from getting presented to advertisers. It can be done by creating ads.txt on all of your registered domains.

We strongly suggest that your website have ads.txt. It can help advertisers determine counterfeit inventory and assist you to receive even more advertiser spend that may have otherwise eliminated toward that counterfeit inventory.

Why ads.txt was introduced?

The digital marketing industry is constantly attempting to ensure that bad visitors will be kept out of websites. Also, it greatly helps legitimate publishers ensure and grow their website’s revenues by using an it in the domain’s root directory

It is a text file that publishers may host on the web servers. Listing the others authorized to market their products. This is made to allow online purchasers to check on the validity of the retailers from whom they purchase, for the reasons of internet fraud avoidance.

IAB(Interactive Marketing Bureau Tech Laboratory)

The IAB’s ads txt specification dictates the formatting of ads.txt. It may contain 3 types of records; data records, comments, and variables. An ads txt can include a variety of information, each placed on a separate line.

It specifies a mechanism for content publishers & is used by webmasters to list their authorized digital sellers. It is introduced to fight against fraud and misrepresented domains. ads.txt specification version 1.0.2  provides a way to publishers that if they do not authorize any sellers for their ad inventory.

What’s the task of ads.txt initiative of  IAB?

The mission of the ads txt initiative is to boost transparency in the programmatic ad marketing ecosystem.   It is a straightforward, flexible and secure technique that publishers and distributors can use to publicly declare the firms they authorize to market/sell their digital ad inventory.

By creating a public record of Authorized Digital Sellers, It will generate greater transparency in the inventory source chain. It also presents the publisher’s control over its inventory in the market. It also makes it harder for awful actors to benefit from selling counterfeit inventory across the ecosystem. As publishers adopt it, buyers can easier identify the Authorized Digital Sellers for a participating publisher. It allows the brands to have the self-confidence that they are buying genuine publisher inventory.

What’s ads.txt file?

Ads.txt is a straightforward, flexible, and secure way for publishers and distributors to declare who’s authorized to market their inventory.  Thus, enhancing transparency for programmatic buyers for their ads management.

Ads.txt helps transparent programmatic digital media transactions. It also removes the monetary incentive from offering counterfeit and misrepresented media. Like robots.txt, It is posted to a domain by a publisher’s webmaster, which makes it valid and authentic.  ads.txt is simple to update, which makes it flexible. The data necessary to populate the document is easily available in the OpenRTB protocol. It makes ads.txt simple to gather and target it. And publishers sell their inventory through a number of sales channels.

More about ads.txt?

Ads.txt is a significant brand safety tool. It is introduced to battle inventory fraud and improve transparency in the wonderful world of digital marketing. This essentially labels who’s and isn’t authorized to market traffic from a site. It guarantees that your site inventory is guarded against fraud and comes only through “authorized marketing systems.”

How does ads.txt work?

how ads.txt works

Ads.txt helps to create a publicly accessible record of authorized digital sellers for publisher inventory. It is helpful that programmatic buyers may index and reference if indeed they wish to buy inventory from authorized sellers. Further, participating publishers must post their set of authorized sellers to their domain home directory. Programmatic purchasers can then crawl the website for publisher’s ads.txt. They then create a listing of authorized sellers for every participating publisher. After that programmatic buyers can create a filtration system to match their ads.txt list against the info provided in the OpenRTB bid request.

A buyer getting a bid-ask for claiming to become may verify if the exchange and SellerAccountID fit the authorized retailers listed in

How does ads.txt function?

Publishers place a textfile on their web hosting servers. It lists all the businesses that are authorized to market the publishers’ ad inventory. Likewise, programmatic systems also integrate with ads txt files. It is to verify which publisher’s inventory they are authorized to market. This allows potential buyers/purchasers to check on the validity of the inventory they buy.

How come ads.txt is important?

ads.txt is essential for almost all publishers. ads txt on the website says which businesses can sell inventory. It offers complete permission control. Therefore making it more challenging for fraud that may occur. An ads txt provides publishers with an increase of advertiser spend by eliminating the prospect of fraud inventory.

Why should I use ads.txt?

The ads.txt document can help you protect your site from fraud inventory.

Quite simply – using ads txt file certainly helps you to get you to even more advertiser spend that may have in any other case gone toward fraud inventory.

What should I do if my website already has ads.txt?

If your website currently has ads.txt @ domain’s root directory, you have nothing to do.

How do you create an ads.txt for your website?

Implementing ads.txt is low-cost and incredibly easy.

To create an ads txt, please follow the instructions below:

Create a text message (.txt) file and place it at Your domain’s home directory.

For instance, ads.txt

What information goes into an ads.txt document?

For every authorized seller, there must be an entry in a separate line of ads txt file. Each collection in a publisher’s ads.txt list requires 3 bits of data (and also a fourth field, which is an optional field):

#1FIELD: Domain name
# 2FIELD: Publisher’s accounts ID
# 3FIELD: Accounts type (DIRECT/RESELLER)
#4FIELD  (Optional): Сertification Authority ID, if obtainable.

What does ads.txt contain?

Lets assume a website with name It published an ads txt on their web server. It lists three exchanges as authorized to sell their ad inventory, including’s seller account IDs within each of those exchanges. contains the below information.
#< SSP/Exchange Domain >, < SellerAccountID >, < PaymentsType >, < TAGID >, 3200000 , DIRECT, 20300, RESELLER, 0bfd66d529a55800, pub-6373315980741255, RESELLER, f08c47fec0942abc

Please note that, The seller’s Publisher.ID will end up being specified in the “SellerAccountID” field in the ads.txt.

How do buyers use ads.txt to check on who is authorized to market?

Lets assume both exchange and the publisher each adopt ads.txt.  Bidders may check their tags for the existence of an ads.txt document to verify that the exchange and publisher possess the best connection to one another.

What are the Best Practices of an ads text file?

Depending on your website audience size you may have a different perfect practice to adhere too. Many publishers need to boost income and advertiser demand and prices on the site and therefore use many ad suppliers and add many ads txt files to improve competition and income. That is perfectly suitable and there is absolutely no downside to doing this. Other large publishers limit their ads.txt additions to control sales team competition and conflicts. Based on your objective will determine the very best practice.

Any kind of drawbacks?

It depends upon who you ask this question. For SSPs that thrive on undisclosed reselling, this initiative can slice to their business if it alerts the purchase side with their shady practices.

if in case buyers identify inventory that isn’t called valid, the reject the request.

How about drawbacks for businesses that aren’t shady?

As we all know, Publishers and exchanges already stretching their programmer resources. They will need to allocate a web programmer to integrate these text files. It also requires them to monitor whenever publishers alter their lists of authorized retailers.


The Interactive Marketing Bureau Tech Laboratory introduced a file called ads.txt. It is a tool that will help ad buyers avoid illegitimate sellers who arbitrage inventory and spoof domains illegally. Usually, Publishers put a file on their server. It says precisely which companies they offer their inventory through.

It lists partners by name & also contains the publisher’s account ID. This is actually the same ID buyers (marketers) observe in bid demand. If in case you’re using more than one ad network, be sure you put that network to your ads txt file. Get in touch with your ad network for his or her ads.txt information.

Therefore, It is extremely recommended to utilize the ads txt file initiative as a responsible publisher. It is made to combat inventory fraud and improve transparency in the digital marketing industry.

ads.txt file: A Tool for Digital Ad Inventory