Security / Verify a document
Verify a signed document.
Did you receive a PDF that says it was signed with Plutosign? Check it here. You do not need an account.
Drop the signed PDF here
The file stays on your device. Only its fingerprint is sent.
How the check works
- Your browser reads the PDF and calculates its SHA-256 fingerprint. The file does not leave your device.
- Your browser sends only the fingerprint to Plutosign.
- Plutosign compares it with the fingerprint it stored for each completed document.
A match tells you the date that signing completed, the number of signers and whether the Certificate of Completion is attached. It does not show the document title, names, email addresses or the company that sent it.
What a match proves
A match proves that this exact file is the one Plutosign stored when signing completed. If one byte of the file changes, the fingerprint changes and the check shows no match.
What a match does not prove
A match does not prove who signed, beyond what the audit trail records. The Certificate of Completion at the end of the signed PDF lists the audit trail: the signers, the signing events, timestamps and IP addresses.
No match does not prove that a file is fake. A file can be different because someone re-saved, printed or compressed it, because it is not the final signed PDF, or because it was completed before Plutosign started to store fingerprints.
Read more about signing evidence and the security controls.