Digital Signature
Add X.509 digital signatures to PDF documents. Sign PDFs with PFX, P12, or PEM certificates for legal validity.
Upload PDF to Sign
Drag and drop a PDF file here, or click to browse.
About This Tool
Digital Signature allows you to add cryptographic X.509 digital signatures to PDF documents. Unlike simple drawn signatures, digital signatures provide legal validity and document integrity verification.
Upload your certificate file (PFX, P12, or PEM format), enter the password, and sign your PDF. You can add visible signatures with custom text, images, and positioning, or invisible signatures for document integrity only.
All signing happens locally in your browser. Your certificate and documents are never uploaded to any server.
How to Use
Upload PDF
Upload the PDF document you want to digitally sign.
Load Certificate
Upload your X.509 certificate file (.pfx, .p12, or .pem) and enter the password.
Configure Signature
Optionally add reason, location, and visible signature with custom text or image.
Sign and Download
Click Sign PDF to apply the digital signature and download the signed document.
Use Cases
Legal Documents
Sign contracts, agreements, and legal documents with legally binding digital signatures.
Business Approvals
Digitally sign invoices, purchase orders, and approval documents for audit trails.
Document Integrity
Ensure documents have not been tampered with after signing.
Frequently Asked Questions
What certificate formats are supported?
PFX (.pfx), PKCS#12 (.p12), and PEM (.pem) certificate formats are supported.
Is the signature legally valid?
Yes, X.509 digital signatures are legally recognized in most jurisdictions when using a valid certificate.
Can I add a visible signature?
Yes, you can add a visible signature with custom text, image, position, and styling.