Seller.json Inspector
Fetch an SSP or exchange seller.json file and inspect the seller records, seller types, and obvious missing-field issues. Use it alongside ads.txt reviews when you need a clearer supply-path view of who is represented in a platform's seller file.
Inspect seller.json fields so ads.txt debugging has supply-path context.
What you can do here
- Inspect an exchange during onboarding.
- Review whether a seller file contains expected publisher and intermediary records.
- Support supply-path optimization or audit work.
Before you start
- Enter a domain such as `openx.com` or `pubmatic.com`.
About Seller.json Inspector
The Seller.json Inspector fetches a live seller.json file and summarizes the sellers it contains, including publisher vs intermediary counts and obviously incomplete records.
Use it to add transparency context to ads.txt and reseller investigations.
Best uses for Seller.json Inspector
- Inspect an exchange during onboarding.
- Review whether a seller file contains expected publisher and intermediary records.
- Support supply-path optimization or audit work.
How to use Seller.json Inspector
- Enter an SSP or exchange domain.
- Fetch seller.json.
- Review seller counts, types, and obvious missing-field issues.
What to paste in
- Enter a domain such as `openx.com` or `pubmatic.com`.
What you should see
- Seller counts and a preview of live seller records.
Example checks
These are simple checks you can run when you want a real sample and a clear result to compare against.
Enter a domain such as `openx.com` or `pubmatic.com`.
Why run it: Inspect an exchange during onboarding.
What to look for: Seller counts and a preview of live seller records.
Seller.json and Supply-Path Transparency in Practice
What seller.json adds to ads.txt
Ads.txt tells the market who is authorized to sell a publisher's inventory. Seller.json adds context by describing who those sellers are inside a platform's ecosystem. In a modern supply chain with publishers, intermediaries, and confidential arrangements, that extra context matters. It helps buyers and publishers understand whether a seller is a direct publisher, an intermediary, or something more opaque.
For troubleshooting teams, seller.json is valuable because it makes supply-path discussions less abstract. When an ads.txt entry points to a seller ID, the corresponding seller.json file may reveal whether that ID belongs to a publisher account, a network, or another intermediary layer. That is useful during audits, onboarding, and supply-path optimization because it grounds discussions in documented platform metadata rather than assumptions.
The challenge is that seller.json files can be large, unevenly maintained, and not especially pleasant to inspect manually. An inspector tool helps by surfacing the counts and fields that matter most first, then making it easy to spot incomplete or suspicious records.
How seller-file inspection helps operations
A seller-file review is rarely the very first step in an incident, but it becomes valuable quickly when teams are trying to understand who sits in a chain. If an ads.txt file contains a seller ID that appears unclear, seller.json can provide additional confidence about the entity type and the platform structure surrounding it. This is particularly useful when publishers are reviewing multiple intermediaries and want a clearer transparency picture.
Inspection also supports cleanup and governance work. Platforms sometimes publish files with incomplete fields, legacy entries, or many intermediary records that are hard to interpret from raw JSON alone. Summaries such as total sellers, publisher count, intermediary count, and obviously incomplete rows make the file more approachable and help teams focus on the records most relevant to their investigation.
For supply-path optimization conversations, seller.json inspection adds weight to the question of whether an intermediary path is necessary or expected. It does not answer that question by itself, but it helps frame it with better evidence than a seller ID alone.
Why seller.json review should be paired with other tools
Seller.json is most powerful when used alongside ads.txt analysis rather than instead of it. Ads.txt establishes authorization. Seller.json helps interpret the authorized entities. Together they give a more useful picture of the public supply chain than either file provides alone. That combination is especially helpful during publisher onboarding, buyer audits, and suspicious-reseller investigations.
It also pairs naturally with redirect and wrapper analysis. Once you know who appears in seller files and who appears in request paths, you can compare the two views of the ecosystem. Are the intermediaries you see in wrappers or redirects the same kinds of entities reflected in public seller metadata? If not, that gap may deserve closer review.
The long-term value of seller.json inspection is transparency literacy. Teams that regularly read these files become better at identifying unusual supply patterns and better at explaining them internally. That makes future audits and monetization reviews faster and more credible.
Troubleshooting
What to look for
- Seller counts and a preview of live seller records.
Common issues
- A valid seller.json file can still be incomplete for your specific troubleshooting case.
Best practices
- Include the full URL (with https://) for best results.
- If a fetch fails, confirm the endpoint is publicly reachable.
- Some hosts block automated requests; try a different URL if needed.
Related tools
More tools in the ads.txt category.
- Ads.txt Analyzer - Fetch a publisher's ads.txt file, verify that it exists, lint the syntax, and surface duplicate or missing seller signals that can confuse buyers. Built for publisher monetization teams and ad-ops engineers who need a fast first pass on seller-file health.
- Ads.txt Duplicate Seller Detector - Identify repeated exchange-domain and seller-ID pairs in ads.txt files, including conflicting DIRECT and RESELLER declarations that make publisher authorization harder to reason about.
- App-ads.txt Analyzer - Fetch a live app-ads.txt file from an app developer domain, lint the seller lines, and surface malformed or duplicate records before mobile monetization QA starts.
- Ads.txt Hosting Checker - Check where a publisher ads.txt request really resolves, whether the final host and path stay correct, and whether hosting or redirect behavior is likely to confuse crawlers or buyers.
Related reading
More specific pages for the exact jobs this tool supports.
Inspect Seller.json During Supply-Path Audits
A practical way to read seller files without manually digging through raw JSON.
Verify Seller Type During an SPO Review
A supply-path optimization workflow for seller-type validation.
Inspect Missing Seller Names in Platform Metadata
A niche seller.json page for incomplete public metadata.
Compare Seller.json Files Across SSP Domains
A comparative seller.json workflow for multi-SSP reviews.
Check Confidential Seller Records During an Audit
An audit-focused seller.json workflow for confidential or opaque records.
Verify Seller Domains Before a Buyer Escalation
A buyer-facing seller.json workflow for domain and entity verification.
Check Ads.txt Before Onboarding a Publisher
Use the Ads.txt Analyzer before assuming a publisher seller file is clean and buyer-friendly.
Clean Duplicate Sellers in Ads.txt
Use grouped duplicate records to turn a messy ads.txt file into a prioritized cleanup plan.
Frequently asked questions
Is it free to use?
Yes. Core tools are free and accessible without signup.
Does it upload my data?
This tool makes server-side fetches to the URLs you provide so results can be rendered. We do not store the fetched content beyond the request.
What if I spot a bug?
Please reach out via the Contact page with a reproduction example.
Does it validate the full IAB schema?
It performs practical field checks rather than a full formal schema validation pass.
Can it inspect any domain?
It fetches `https://domain/seller.json` for the domain you provide.
Why pair this with ads.txt?
Ads.txt shows authorization while seller.json helps interpret who the sellers are in the chain.
Helpful links
Standards & references
Official specs that inform how this tool interprets data.