PDF signature checker
Check and verify PDF digital signatures
TL;DR
What is PDF signature checker?
A PDF digital signature is a cryptographic mechanism defined in the PDF specification (ISO 32000) that binds a signer's identity to a document and detects subsequent modifications. It uses a public-key certificate to produce a hash of the document content at the time of signing.
Common use cases
- ‣Contract validation: confirm that a signed PDF has not been altered after the signature was applied
- ‣Regulatory compliance: verify that official documents (invoices, certificates, legal filings) carry a valid digital signature
- ‣Certificate inspection: view the signer's certificate details including issuer, validity period, and signature algorithm
Frequently asked questions
What is the difference between a digital signature and an electronic signature?
A digital signature is a cryptographic construct: it uses a certificate and private key to produce a verifiable proof of identity and document integrity. An electronic signature is a broader legal concept that includes scanned handwritten signatures, typed names, or click-to-agree checkboxes. Digital signatures are a specific, high-assurance type of electronic signature.
Does this tool upload my PDF to a server?
No. The PDF is read and analyzed entirely in your browser. The file bytes never leave your device.