What is ads.txt

ads.txt helps buyers verify they're purchasing legitimate ad inventory. Publishers list every authorised seller in a plain text file.

Each seller record has three required comma-separated fields and an optional certification-authority ID: exchange.com, pub-id, DIRECT|RESELLER[, cert-id]. ads.txt 1.1 variables and extensions may also appear.

If the publisher authoritatively declares that no advertising system is authorised, ads.txt 1.1 defines placeholder.example, placeholder, DIRECT, placeholder as the no-seller placeholder. A blank file is not that declaration. Use authorised publisher information for seller IDs and relationships. Flowpane’s syntax assessment does not certify external seller authority.

When to use it

Establish whether this Site sells advertising, then obtain the correct advertising-system domain, account ID and relationship from the responsible publisher or partner.

If a partner gives you a replacement account ID, confirm it with the publisher before preparing the change; do not infer it from another website.

Location and responsibility

Use the root /ads.txt address and confirm which CMS, plugin or file serves it. A syntactically valid record does not prove a commercial relationship, prevent all fraud or certify a seller. A Site with no advertising needs a relevance decision, rather than fabricated seller records.

Refer to IAB Tech Lab ads.txt for the external specification or convention. Use Flowpane’s check details to understand what its own assessment covers; a product score is not a certification.