Inspect C2PA Content Credentials
Find out whether a file carries a signed record of how it was made, who signed it, and whether anything has changed since. The validator runs on your device.
The tool
What this checks
Content Credentials are a signed record of how a file was made, embedded in the file itself. This reads that record and checks it against the file’s actual bytes.
The validator is about 8 MB of WebAssembly, so it is only downloaded once a file is found to actually contain a manifest. It runs on your device, and the certificate lists it checks against are served from this site rather than fetched from anyone.
The two questions people confuse
Nearly every mistake made with Content Credentials comes from collapsing two different checks into one verdict.
Has the file changed?
The manifest contains a hash of the file’s bytes. If they still match, nothing has been altered since signing. This is a fact you can verify offline, and it is the strongest single thing provenance gives you.
Do we recognise the signer?
Whether the certificate chains to an authority on the C2PA trust list. A file can be perfectly intact and still fail this, simply because its signer has not joined the programme. It is not a tampering signal.
Where the AI signal actually lives
The presence of a manifest does not mean a file was AI-generated. It only means someone recorded its history. The field that actually says so is digitalSourceType on the c2pa.actions assertion, carrying the IPTC value trainedAlgorithmicMedia. That is what this tool surfaces prominently, and it is a declaration by the producer rather than a detection.
Where the manifest sits in each format
A cheap scan looks for the carrier before anything else, so the 8 MB validator is only downloaded for files that actually have one: JPEG stores it in an APP11 segment, PNG in a caBX chunk, WebP and other RIFF containers in a C2PA chunk, MP4 and HEIC in a uuid box, SVG in a c2pa:manifest element, and TIFF in a private tag.
Common questions
- What are Content Credentials?
- A signed record of how a file was made, embedded inside the file itself and cryptographically bound to its bytes. The standard is C2PA. A manifest can say which tool produced the file, what was done to it, what it was built from, and whether it was generated by an AI model.
- The signature is valid but the signer is "not on a recognised trust list". Is the file fake?
- Almost certainly not. Those are two separate questions and this tool shows them separately for exactly that reason. "Unmodified since signing" is a mathematical fact about the bytes. "Recognised signer" depends on a certificate programme that is young and thinly populated, so many genuine files fail it.
- Why does it say revocation was not checked?
- Checking whether a certificate has been withdrawn requires contacting the issuing authority, which a browser cannot do for these certificates. Rather than quietly implying everything is fine, the result says the check did not happen.
- No credentials were found. Does that mean the file is not AI-generated?
- No. An absent manifest is not evidence either way. Credentials are stripped by almost any ordinary re-save, screenshot, format conversion or social platform upload, and most software never adds them in the first place.
- Can I remove or re-sign credentials here?
- Removal is available in the metadata tool, behind an explicit warning, because it is irreversible. Re-signing is not offered and never will be. Forging provenance is the one thing this tool exists to make harder, not easier.