How to Validate a Digital Signature in a PDF
Validating a digital signature answers two questions: is the document unchanged since it was signed, and can the signature be trusted? PDF Verified checks the document fingerprint and the signing record so you get a clear, plain-language verdict.
Step by step
- Open /verify and upload the PDF.
- The checker reads the embedded signature record and fingerprint.
- See whether the signature is valid and the document intact.
- Expand the audit trail for the full chain of custody.
What to look for
- Document integrity confirmed by the SHA-256 fingerprint
- A signing record with time and signer identity
- No content added after the signature
- A verification page that resolves and is not revoked
Frequently asked questions
Is it free to validate a digital signature?
Yes. Upload the PDF to the PDF Verified checker and get a verdict for free — no account needed. The file is analysed and not shared.
Do I need the original to compare against?
No. If the document was sealed by PDF Verified, the SHA-256 fingerprint is embedded and checked automatically. For any other PDF, the forensic checker inspects the file's own structure, metadata, and revision history.
Is my document kept private?
The file is processed only to produce the verdict and is not published or shared. Verification of a PDF Verified document can also be done with just the QR code or short code — without uploading the file at all.
More verification guides
- How to Check if a PDF Was Edited or Modified
- How to Verify a Signature Is Authentic
- How to Detect Document Tampering & Forgery
- Verify a Signed PDF Online — Free
- How to Check Document Authenticity Online
- How to Check PDF Metadata & Edit History
- How to Verify a Certificate of Completion
- How to Tell if a Document Was Photoshopped or Altered
- Verify a Document Without an Account or Software