Drop signed PDF here
Select a PDF with a visible digital signature. The preview shows the result before download.
Signature details from the original PDF
Green tick copy ready
Validate a PDF Signature Online and Fix a Yellow Question Mark
Does a downloaded PDF show a yellow question mark or "Validity Unknown" where you expected a green tick? That symbol alone does not prove the document was changed. A PDF viewer may be unable to establish the signer's certificate trust or complete every validation step. This tool checks the embedded digital signature in your browser and, for a supported signature appearance, previews a green-tick display copy.
What this PDF signature checker does
- Checks document integrity: verifies that the embedded CMS digital signature matches the protected PDF bytes.
- Checks final-revision coverage: rejects a file if the final PDF contains bytes beyond all verified signed ranges.
- Shows actual signature details: displays the signer, certificate issuer, serial number, validity dates, fingerprint, algorithms, claimed signing time, and signed byte ranges.
- Creates a consistent visual copy: replaces a supported unknown-status graphic with a green check and "Signature valid" title, then downloads a flattened PDF for viewing or printing.
This is an integrity and appearance tool, not a complete certificate-trust service. It does not build a chain to India's Controller of Certifying Authorities (CCA) root, check revocation, validate a QR code, or confirm an issuing portal's records. The certificate dates are reported separately from the cryptographic result.
How to check a PDF digital signature online
- Select a PDF with an embedded digital signature. An image of a handwritten signature or a QR code alone is not enough.
- Read the integrity and coverage results, then open Show Signature Details to inspect the signer and certificate.
- Preview the page before downloading the green-tick display copy. Keep the original signed PDF for later verification.
Indian government PDFs and supported files
Government PDFs from services such as e-District, DigiLocker, Aadhaar, and tax portals can use different signing and appearance formats. This tool's green-tick conversion has been tested with a West Bengal e-Ration Card PDF that contains an Adobe-style question-mark appearance. Support for e-Aadhaar, PAN e-cards, certificates from other states, password-protected PDFs, and QR-only documents is not guaranteed. If a file is unsupported, the tool leaves the original appearance unchanged and explains why.
Frequently asked questions
Why does Adobe show "Validity Unknown" or a yellow question mark?
Adobe evaluates more than whether the signed bytes match. It also considers signer certificates and trust settings. An unknown status can mean those checks were not completed; it is not, by itself, proof that the PDF was altered. This tool reports its narrower checks separately.
Will this turn every digital signature into a green tick?
No. The cryptographic signature must match, the final revision must be covered, and the PDF must use a supported question-mark appearance. A scanned signature, unsupported layout, or failed check will not produce a green-tick copy.
Does an expired signer certificate automatically mean the file was modified?
No. Certificate validity dates and document integrity are different questions. The tool shows whether the certificate was within its validity dates at the PDF's claimed signing time, but it does not establish a trusted timestamp, certificate chain, or revocation status.
Is the downloaded green-tick PDF still digitally signed?
No. The download is a flattened visual copy whose tick should look the same in different viewers and printouts. The cryptographic signature remains in your original PDF, so retain that file and use it for formal verification.
Are my PDFs uploaded or stored?
No. The PDF is processed in browser memory and is not uploaded by this tool. An internet connection is used to load its PDF libraries.