Verify the signatures of a PDF file. A signed PDF file contains one or more signatures that may be used to determine whether the contents of the file have been altered since the file was signed.
A PDF digital signature uses public key cryptography to verify the signer identity and that the document has not been altered since signing.
No. The PDF is processed entirely in your browser. Your file never leaves your device.
A digital signature uses PKI cryptography with a CA to verify signer identity — legally binding and tamper-detectable. An electronic signature is broader (scanned handwriting, online platforms). This tool checks PKI-based PDF digital signatures.
A digital signature uses a PKI certificate (e.g., X.509) to cryptographically sign the PDF, enabling verification of the signer's identity and document integrity — it has strong legal standing. An electronic signature is a broad term covering signature images, click-to-agree, etc., with no cryptographic guarantee. Many jurisdictions legally recognize digital signatures that meet specific criteria. PDF digital signature verification requires trusting the issuing CA's root certificate.