In this article, I will follow a guide from IAB Tech Lab to create an Ads.txt file for a site which does not have authorized advertising system records, which is the case for The New Leaf Journal (we are proudly ad-free). My article comes with a prefatory story, but you can jump to the solution if you came here just looking for a way to add a properly formatted Ads.txt file to an ad-free site.
Introduction
Many websites have an Ads.txt file to list authorized digital sellers. The Ads.txt file is an initiative of IAB Tech Lab and supported by Google, one of the two dominant players in the digital ad space. Like many (if not most) sites around the web, The New Leaf Journal has a robots.txt file for the purpose of advising our non-human visitors how they should behave (see our robots.txt file). Back in 2022, I wrote about implementing a fun humans.txt file for our human visitors (see our humans.txt file). On December 1, 2025, I added an even more niche carbon.txt file after having learned of the existence of the carbon.txt standard while viewing server logs (see our carbon.txt file). In that article, I noted that I decided to add a carbon.txt file with the goal of collecting all of the somewhat common website .txt files. With the carbon.txt box checked, let us add an Ads.txt file.
Wait… you don’t have ads!
Some readers may have done a double-take when I said “let us add an Ads.txt file.” If you are reading this article on our website, you may notice that there are no ads on the page. The ad-free trend continues on other New Leaf Journal pages. To be sure, The New Leaf Journal has never had ads or affiliate links. Am I going to the dark side? Is that why I am adding Ads.txt? Fear not, as I said in the previous paragraph, I am adding an Ads.txt file to collect all the text files.
A Proper Ads.txt Introduction
IAB Tech Lab describes the purpose of the Ads.txt file:
The mission of the ads.txt project is simple: Increase transparency in the programmatic advertising ecosystem. Ads.txt stands for Authorized Digital Sellers and is a simple, flexible and secure method that publishers and distributors can use to publicly declare the companies they authorize to sell their digital inventory.
How does Ads.txt actually work? I again turn to IAB:
Ads.txt works by creating a publicly accessible record of authorized digital sellers for publisher inventory that programmatic buyers can index and reference if they wish to purchase inventory from authorized sellers. First, participating publishers must post their list of authorized sellers to their domain. Programmatic buyers can then crawl the web for publisher Ads.txt files to create a list of authorized sellers for each participating publisher. Then programmatic buyers can create a filter to match their Ads.txt list against the data provided in the OpenRTB bid request.
In short, IAB Tech Lab maintains a specification for the Ads.txt file which both humans and machines can read to understand which digital sellers are authorized to place ads on the website in question. The website must place the Ads.txt file somewhere that is accessible to crawlers. In our case, we will be placing it in our site’s root directory so that it is available at https://thenewleafjournal.com/ads.txt (which is where our other “.txt” files are placed). For those who are interested in digging deeper, I recommend perusing the resources on IAB Tech Lab since I have not looked too deeply into the specification for reasons noted in the previous section.
Creating Ads.txt for The New Leaf Journal
Before continuing, I note that I did previously have an Ads.txt file which stated in prose that we do not have ads (beyond noting that we, usually Victor V. Gurbo, may use NLJ to discuss other projects). But I was not satisfied with that Ads.txt file. What I want is a properly formatted Ads.txt file indicating that we do not sell ad space.
IAB Tech Lab publishes PDFs with the full Ads.txt specification and implementation guidelines. The current version of the Ads.txt specification is 1.1, which was published in August 2022. We want to be up to date, so I opened up the version 1.1 PDF.
The PDF is 23 pages. While I am sure that all 23 pages are very important for many websites, I was looking for a specific part of the specification. In order to find that part, I pulled up the page search bar in Firefox and looked for “no ad.” This query proved to be fruitful. I immediately jumped to section 3.2.1, titled FILES WITHOUT AUTHORIZED ADVERTISING SYSTEM RECORDS. I present a screenshot of the section below.
IAB Tech Lab explains that previous versions of the Ads.txt specification recommended publishing an empty Ads.txt file. However, the new version changed the guidance and now recommends adding “at least one properly formatted line which adheres to the format specification…” Better yet, IAB Tech Lab provides a line for sites like mine to copy and paste into the Ads.txt file:
placeholder.example.com, placeholder, DIRECT, placeholder
Things like “placeholder” or “example.com” are usually supposed to be replaced. When I first saw the line, I assumed that I would need to replace something. Not so says IAB Tech Lab:
The domain “example.com” bears no significance: it is used here so that the line will start with a properly formatted, permanently reserved (https://tools.ietf.org/html/rfc6761) alternative domain to a real advertising system.
The provided link goes to a resource which notes that example.com, example.net, and example.org are permanently reserved domains. I suppose that we could replace example.com with example.org or a different permanently reserved domain, but I decided to stick with the IAB Tech Lab example.
Adding a Comment
We have created an Ads.txt file that will be intelligible to machines. However, it occurred to me that human readers who stumble upon our Ads.txt file (unlikely, but stay with me here) may find a file including nothing but placeholder.example.com, placeholder, DIRECT, placeholder confusing. I dare say it could even be misinterpreted. One may think I have plans to fill in the placeholder. Is there a way that I could add an explanation without breaking the formatting? Indeed there is. Section 3.2 of version 1.1 of the Ads.txt specification (right above section 3.2.1) notes that “Lines starting with # symbol are considered comments and ignored.” With that in mind, I added the following comments to our Ads.txt file:
# The above line indicates that we do not sell ad space pursuant to v1.1 Ads.txt specification (https://iabtechlab.com/wp-content/uploads/2022/04/Ads.txt-1.1.pdf)
# Learn more at https://thenewleafjournal.com/b/DpKThe first comment explains the purpose of our placeholder line and the second links to this article (the shortlink comes courtesy of the Hum plugin for WordPress, which I discussed in an article about our TWTXT feed). This will enable human visitors who happen upon our Ads.txt file (again, unlikely, but you never know) to learn more while being reassured that their ad-blocker can take it easy on The New Leaf Journal.
Uploading Ads.txt to The New Leaf Journal
After carefully creating our Ads.txt file by copying the no-advertising line from IAB Tech Labs into a plain text document titled ads.txt, I dropped it into the root directory of The New Leaf Journal. You can now view it at https://thenewleafjournal.com/ads.txt. I added a similar Ads.txt file to our short-form publishing sister site, The Emu Café Social (https://social.emucafe.org/ads.txt) (the only difference is that I link to an article on ECS instead of here for the second explanation link).
Conclusion
While The New Leaf Journal continues to be an ad-free publication, it now has a properly formatted Ads.txt file. Our new Ads.txt file is unlikely to change anything but I will nevertheless hope against hope that it puts a small dent in the number of spam emails I receive from people (or former Chinese government officials) looking to create “content” for my audience which may include links to casinos or e-bikes.
