Verify PDF signatures
Has the document changed since it was signed, and who signed it? Every digital signature in the PDF is checked, in your browser.
Your files never leave your browser. Nothing is uploaded, anywhere.
Drop your PDF here
or
No limit on file count or size — only your computer’s memory.
How it works
- Drop in the signed PDF.
- Read the check of each signature.
Questions
- What does “valid” mean?
- That the document is intact since it was signed, and that the signature was made with the key of the certificate shown. The tool doesn’t say whether you should trust that certificate: it checks no list of authorities and no revocations, since it connects to nothing.
- Changes “after the signature”?
- A PDF can get new revisions after it is signed: another signature, a filled-in form, comments. The signature stays valid for what it signed; it is up to you to judge what was added.
- What about Adobe Reader?
- Adobe also checks how far certification authorities are trusted, using its own list. The two checks complement each other.
- Is my document uploaded?
- No — the whole check happens in your browser.