- How can I verify a PDF signature without Adobe Acrobat?
- Use the checker on this page: select the signed PDF and it validates the signature in your browser — no install, no account. It reports validity, signer identity, certificate issuer, signing time, and whether the document changed after signing. Acrobat remains useful as a second opinion for full trust-chain validation on business-critical documents.
- Can I verify PDFs signed with DocuSign, Adobe Sign, or similar platforms?
- Yes. Those platforms embed standard PKCS#7/CMS digital signatures, which this tool parses and verifies. The certificate details will show the platform's certificate authority (for example DocuSign's CA) as issuer, plus the signing timestamp the platform applied.
- What does 'document modified after signing' mean?
- The content hash no longer matches what was signed — something in the document changed after the signature was applied. Sometimes it's benign (a form field filled in, or a second signature appended after the first); sometimes it's exactly the tampering the signature exists to catch. Treat it as a stop-and-ask: request the original signed file from the sender and compare.
- Is it safe to verify a confidential contract here?
- Yes — the file never leaves your machine. Parsing and verification run in client-side JavaScript in your browser, with no upload. That's the specific reason to use a no-upload verifier for legal and commercial documents instead of services that process the PDF server-side.
- The signature is valid but from a certificate I don't recognize. Now what?
- A valid signature proves the document is unchanged and was signed by whoever controls that certificate — it doesn't prove the certificate belongs to who you think. Check the issuer field: a known CA (DigiCert, GlobalSign, Sectigo, a government or platform CA) is what you want. A self-signed or unknown-issuer certificate on an important document warrants verifying the signer's identity through another channel.
- Is this tool free?
- Yes — free, no signup, no file-size games, and no upload: the PDF is analyzed entirely in your browser, which is exactly what you want for confidential signed documents.
