About Verify PDF Signature
Verify Digital Signatures in Any PDF
Received a signed PDF and want to check if the signature is real? Our free PDF signature verifier analyzes the internal structure of your document to detect both cryptographic digital signatures and visual (image-based) electronic signatures.
What This Tool Checks
- Digital signatures — Detects AcroForm /Sig fields containing PKCS#7 or CAdES cryptographic data, including signer name, signing date, reason, and location.
- ByteRange integrity — Verifies whether the signature's ByteRange covers the entire file, which indicates the document has not been modified after signing.
- Visual signatures — Scans the last page for embedded images that may represent a visual signature stamp.
- Document metadata — Shows producer, modification date, page count, and annotation count for additional context.
When to Use This Tool
- You received a contract or NDA and want to confirm it was digitally signed
- You need to verify whether a PDF has a cryptographic or just a visual signature
- You want to check if a signed document was tampered with after signing
- You need to inspect signer certificate details before trusting a document
Privacy First
All verification runs locally in your browser using pdf-lib. Your signed contracts, legal documents, and sensitive files are never uploaded to any server.