About
Why the mark exists
Detection is losing. Every tool that claims to spot generated media is in a race it cannot win, and the confident ones are the least trustworthy — a detector that is wrong one time in twenty is a detector that will ruin somebody. Synthless does not try to win that race. It works the other way round: it records what could be checked about a file, and it asks a person to put their name to the rest.
That is why the neutral verdict is a declaration rather than a finding. A missing watermark proves nothing. A named human being who has publicly signed for a file, knowing the mark can be revoked in public if they lied, is a real claim — not because signing is hard, but because being accountable for it is.
Who runs it
Synthless is run by a small independent team in Europe. It is not affiliated with Google, Adobe, or the C2PA consortium; SynthID and C2PA are things we check for, nothing more. We take no position on whether generative tools should be used — only on whether a claim about a particular file is true.
The checks run in your browser. Files are not uploaded unless you choose to sign for one, and the verification record keeps the file’s hash rather than the file.