PDF Digital Signer
2025 • Personal
Node.js Next.js PDF Digital Signature Cryptography
Web application for digitally signing PDF documents using PFX certificates with customizable signature placement and Adobe Acrobat compatibility.
Features
- PDF document upload and preview
- Digital signature using PFX (PKCS#12) certificates
- Custom signature position selection on document
- Adobe Acrobat Document (AcroForm) support
- Private key certificate management
- Signed PDF download
Implementation
Users upload a PDF file and their PFX certificate (private key), then visually select the signature location on the document. The application applies the digital signature with proper cryptographic validation, creating a legally valid signed PDF compatible with Adobe Acrobat.
Technical Details
- Frontend: Next.js for interactive PDF preview and signature positioning
- Backend: Node.js for PDF processing and cryptographic operations
- Certificate Format: PFX/PKCS#12 for private key storage
- PDF Standards: AcroForm compliance for signature fields
- Security: Client-side certificate handling with secure signing process
Use Cases
- Document authentication and verification
- Legal document signing workflows
- Contract and agreement validation
- Secure document approval processes
Technologies
- Next.js
- Node.js
- PDF Processing Libraries
- Digital Signature Standards (PKCS#12)
- Adobe Acrobat Document Format (AcroForm)