ProvenanceAll answers
Verify a page
Paste an address. This reads the page and its signed manifest, re-hashes the page in your browser, and checks the signature against the published key. Nothing about the verdict depends on trusting this site: the key is public and the arithmetic happens on your machine.
A page with a manifest can be checked. A page without one answers with the address that was missing.
What this proves, and what it does not
A manifest makes one of two claims, and the verdict above names which. For a page manifest, it proves the
bytes the page served are the bytes that were signed. For a build manifest, it proves the build that renders
that address is the build that was signed, and says nothing about the bytes of any one response, which a
worker assembles per request. Either way it proves the signature was made with the key named in the manifest,
and that the key is one published at
/answers/.well-known/attest/allowed_signers. It does not prove the page is true, that a number on
it is right, or that the person named as its author wrote it.
For a page manifest the signature covers the page's main region rather than the whole response, because the edge appends its own script to every HTML page it serves. The bytes outside the region are counted and shown, not hidden.
The same check runs on the command line, if you would rather not trust a browser:
python3 tools/attest.py --verify <url>.
Version 1.1Signed 12 November 2026ZPEProvenanceCheck this page