ads.txt API
Fetch and evaluate any publisher's ads.txt / app-ads.txt — the IAB authorized-digital-sellers standard. Pass a domain and the check endpoint fetches its ads.txt server-side, then returns every seller record parsed into its fields — advertising system, the publisher's seller/account id, the DIRECT or RESELLER relationship and the optional certification-authority id (TAG-ID) — alongside counts (direct, reseller, distinct ad systems) and the declared variables OWNERDOMAIN, MANAGERDOMAIN, CONTACT and SUBDOMAINS. The verify endpoint answers the one question programmatic-advertising integrations actually ask: is this advertising system, with this publisher id, authorized to sell this domain's inventory? — returning an authorized boolean and the matching records. A missing file is reported as found:false (not an error), and soft-404 HTML pages are detected and rejected so you never parse a "page not found" as records. The request is made server-side and private or internal targets are refused (SSRF-guarded). Built for ad-tech supply-chain verification, SSP/DSP onboarding checks, anti-fraud and inventory audits. An ads.txt seller-authorization checker — distinct from the security-contact file reader (securitytxt), the robots.txt crawlability evaluator (robots) and the sitemap parser (sitemap). No upstream key, no cache.
api.oanor.com/adstxt-api