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Validate Signature

Verify digital signatures in your PDF files. Check certificate validity, view signer details, and confirm document integrity. All processing happens in your browser.

Click to select a file or drag and drop

PDF Documents

Your files never leave your device.

About Validate Signature

Validate Signature checks whether the signed content has changed and shows the signing certificate’s details.

How to use it

  1. Select your PDF, or drag it onto the drop area.
  2. Review each signature’s status and certificate.
  3. Optionally load a trusted certificate to check the chain.

Your file stays on your device

This tool runs entirely in your browser. Your file is read from your device, processed in memory, and saved back to your device — it is never uploaded to Qpdf or anyone else. Once this page has loaded, the tool also works with your internet connection switched off.

How Qpdf keeps files private →

Good to know

  • Qpdf does not contact certificate authorities, so revocation status is not checked.

Related tools

All tools →
Digital Signature Sign with an X.509 certificate (PFX/P12).
View Metadata Inspect a PDF’s hidden properties.