Verifying a signed document

Anybody holding a completed document can check it without signing in and without knowing whose it is.

How to check one

• Open the verify page.
• Upload the completed signed document — the file with the certificate attached, exactly as it was received.
• The answer says whether that file matches a document signed through this product.

You can also paste a SHA-256 hash instead of uploading, if you have one of the finished file. The certificate's own "Certificate reference" is not that, and neither is the "SHA-256 of the document as presented for signature" printed on it — that one is the hash of the document BEFORE it was signed, so pasting it reports no match on a document that is perfectly genuine. Upload the file.

What a match means

The stored document is read back and hashed after it is stored, not before, so what is checked is what storage actually holds rather than what was meant to be put there. A document altered by so much as one byte does not match.