The ads.txt file is a public list of authorized digital sellers for a website. Google describes it as an IAB Tech Lab initiative intended to help publishers identify sellers authorized to sell their inventory. Google says ads.txt is not mandatory, but recommends it. An ads.txt warning is a specific account status to address; it is not, by itself, proof that a site has failed an AdSense content review.
Use the publisher-specific information shown in your AdSense account. Google’s ads.txt guide shows a sample format, but publishers should copy their own account’s line instead of copying a sample publisher ID. The file is generally served at the root URL, such as https://example.com/ads.txt. After uploading, open that URL in a browser and confirm the text is visible. Then return to AdSense and check the status; Google says changes can take time to appear.
Common mistakes include uploading the file into a subfolder, using the wrong publisher ID, adding formatting characters, replacing other networks’ valid seller records, or serving different content on the www and non-www domains. If your site is on WordPress, identify whether the host, plugin, or another service manages the root file before editing so you do not overwrite a working setup.
Example: An owner sees “Not found,” uploads ads.txt to /wp-content/uploads/ads.txt, and expects it to resolve. The file exists, but the expected root path remains empty. Move or configure it so the root URL serves the correct content, then ask AdSense to recheck if the account offers that action.
Use SiteReadyScore to check whether the public ads.txt path is reachable and add that evidence to your technical checklist. Confirm the publisher ID and account status yourself in AdSense; a public scan cannot know whether the line belongs to your account.