Validate PDF Signature
About Signature Validation
Check the digital signatures in a PDF:
- Who signed it (from the certificate)
- When it was signed
- Integrity — whether the content is unchanged since signing
- Trust — whether the certificate chains to a trusted root
Tip: Need to sign instead? Use the Sign PDF tool.
Tips for Best Results
- "Intact" means the document has not changed since that signature was applied
- A signature can be intact yet from an untrusted/self-signed issuer — both are reported separately
- An incremental edit after signing can leave an earlier signature intact but no longer whole-document
- Validation runs entirely on our servers; your file is deleted after processing
- To add a signature, use the Sign PDF tool
Frequently Asked Questions
For each digital signature it reports the signer (from the certificate), the signing time, any stated reason/location, and — most importantly — whether the signature is cryptographically intact, meaning the bytes it covers have not been altered since signing.
The signature is mathematically valid, but the signer's certificate does not chain to a certificate authority trusted by this server (for example a self-signed certificate). The signature can still be intact; trust is reported as a separate, informational status.
Yes. Validation is performed on our own servers and the file is deleted immediately after processing. No third-party service is involved.
Processed on ISO 27001-certified UK servers.
Files are encrypted in transit and automatically deleted.
Learn more