PDF Digital Signature
Apply a cryptographic digital signature to a PDF using a PKI certificate. Unlike a visual e-signature, a digital signature mathematically proves authorship and detects any tampering after signing.
- 1Upload the PDF you want to digitally sign
- 2Load your digital certificate (PKCS#12 / .pfx file) and enter its password
- 3The tool applies a cryptographic signature using your private key
- 4Click 'Apply Digital Signature' to embed the signature in the PDF
- 5Download the signed PDF — recipients can verify authenticity with any PDF reader
- Apply a PKI digital signature to a legally binding business contract
- Sign a regulatory submission PDF with a digital certificate for compliance
- Add a cryptographic signature to a financial report to prove its authenticity
- Digitally sign a software distribution PDF to verify it has not been tampered with
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