How to verify a digital signature in a PDF

Updated August 2026 · ~4 min read

A digitally signed PDF carries a tamper-proof seal from the person or authority that signed it. "Verifying" it means confirming two things: the document has not been changed since signing, and the signer's certificate is genuinely licensed. Here are the two fastest ways to do that in India — online in under a minute, or in Adobe Reader.

Method 1 — Verify a PDF signature online (fastest)

This is the quickest route and needs no software or certificate imports:

1. Open the verifier. Go to the upload box on our home page.
2. Upload your signed PDF. Drag the file in, or click to browse from your phone or computer.
3. Enter the password if prompted. Encrypted files (like e-Aadhaar) show a small popup — type the open password.
4. Click "Verify signature". Within seconds you'll see a Green, Amber or Red verdict, the signer's name, the issuing CA and the signing date.
5. Download the green-tick copy. For a valid signature you can download a flattened copy that opens cleanly in any viewer.

Because we already trust the Indian CCA root certificates, this method confirms signatures that Adobe often labels "validity unknown". Your file is auto-deleted within two hours.

Method 2 — Verify a signature in Adobe Acrobat Reader

If you prefer a desktop reader:

1. Open the PDF in Adobe Acrobat Reader (not a browser preview or basic viewer).
2. Click the Signature Panel button, or the yellow question-mark / signature icon at the top.
3. Right-click the signature and choose Show Signature Properties to see the signer, time and certificate.
4. If it says "validity unknown", click Show Signer's Certificate → Trust and add the issuing certificate (or import the CCA India root) to your Trusted Certificates.
5. Choose Validate Signature (or Validate All). A trusted, unaltered document then shows a green check.

Struggling with the "not verified" warning specifically? Follow our dedicated fix guide.

How to verify an e-Aadhaar signed PDF

UIDAI's e-Aadhaar is password-protected. The password is the first four letters of your name in CAPITALS followed by your year of birth — for example, a person named Raju born in 1988 uses RAJU1988. Upload the file here, enter that password, and the tool validates the UIDAI DSC and shows the signer as UIDAI. The signature confirms the document was issued by UIDAI and hasn't been altered.

How to verify a DSC / e-Mudhra signed PDF

Documents signed with a Digital Signature Certificate (MCA/ROC filings, tenders, audit reports) are issued by CCA-licensed CAs such as e-Mudhra, (n)Code Solutions, SafeScrypt (Sify), Capricorn, XtraTrust and VSign. Upload the PDF and the verifier will identify the CA, trace the chain to the CCA root, and confirm integrity — no manual certificate import needed.

What the green, amber and red verdicts mean

• Green (Verified): the bytes are unchanged and the certificate chains to a trusted CCA root. Fully valid.
• Amber (Untrusted / Modified): the signature is structurally fine but the chain isn't trusted (or an intermediate expired). Treat as a caution.
• Red (Invalid): the file was altered after signing, the signature is corrupt, or there's no signature at all.

Related: Fix "Signature Not Verified" · Our verification methodology · FAQ.