What Are Digital Signatures?

Digital signatures are electronic equivalents of handwritten signatures. They verify the identity of the signer and ensure the document has not been altered after signing. Digital signatures use cryptographic technology to provide security that handwritten signatures cannot match.

How Digital Signatures Work

When you digitally sign a PDF, the signature software creates a unique cryptographic hash of the document. This hash is encrypted with your private key. Anyone can verify the signature using your public key. If the document changes even slightly after signing, the hash no longer matches and the signature becomes invalid.

Benefits Over Handwritten Signatures

Digital signatures are tamper-evident, meaning any alteration is immediately detectable. They verify the signer's identity through digital certificates. They include timestamps that prove when the document was signed. They are legally binding in most countries.

How to Add Digital Signatures

You need a digital certificate from a trusted certificate authority. Our tool supports adding signature fields to PDFs. You can also upload an image of your handwritten signature and place it on the document.

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