PDF Signature Checker

How to Check a PDF Signature

Need to verify that a digital signature in a PDF is authentic and has not been tampered with? Here is how to check it.

Step 1: Upload Your Signed PDF

Drag and drop the signed PDF file into the upload area. The tool will analyze the document and find all digital signatures.

Step 2: View Signature Details

For each signature found, the tool shows you:

• Who signed the document
• When the signature was created
• Whether the signature is valid
• Whether the document has been modified since signing

Step 3: Review Certificate Information

You can view the full certificate details including the issuer, expiration date, and trust status.

Why Verify PDF Signatures

Digital signatures are used to ensure that a document came from the right person and has not been altered. Before you trust a signed contract, agreement, or official document, verifying the signature gives you confidence that everything is legitimate.

The entire verification happens in your browser. The signed PDF is not uploaded to any server.

Common Questions About PDF Signature Verification

What types of digital signatures can be verified?

The tool checks standard PDF digital signatures created with certificate based signing. These are commonly used in legal, financial, and government documents.

Can a valid signature be faked?

A valid digital signature that passes verification has strong cryptographic proof of authenticity. It is extremely difficult to forge. The tool checks the cryptographic chain to confirm the signature is genuine.

What does an invalid signature mean?

An invalid signature could mean the document was modified after signing, the signer's certificate has expired, or the certificate was revoked. The tool explains the reason for the failure.

Do I need any special software?

No. Everything runs in your browser. Upload the PDF and get the results instantly.