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Verify PDF Digital Signature Online Free — PrivaTools

TL;DR: Upload a PDF and see if it carries digital signatures plus signer names — covers detection, not full cryptographic verification.

Inspect digital signature fields in a PDF online for free. Verify signature validity, view signer information, and check certificate details.

Verify PDF Digital Signature is one of 179+ free file utilities on PrivaTools. The entire stack is open source under the MIT license, so the privacy guarantees can be audited end-to-end. You can also run all 179 tools on your own infrastructure with one docker compose command.

How to Verify PDF Digital Signature with PrivaTools

  1. Upload a signed PDF — Drop a PDF with one or more digital signatures.
  2. PrivaTools verifies each signature — Checks that the signed content hasn't been modified since signing, the certificate chain is intact, and the signing date is consistent.
  3. Read the report — For each signature: signer name, signing time, certificate authority, validity status (valid / modified / expired / untrusted CA).

Frequently Asked Questions

Does this require uploading my certificates?

No — verification uses the certificates embedded in the PDF itself, plus the system's trusted CA store.

What if a signature is invalid?

The report says exactly why: content modified, certificate expired, untrusted issuer, or signature format unsupported. The PDF itself isn't rejected — just the signature.

Can I verify multiple signatures?

Yes — PDFs can have multiple signatures (e.g. one per signing party). All are verified independently.

Last reviewed 2026-05-01 by the PrivaTools maintainers. Source code on (MIT-licensed, self-hostable).

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