Check Signatures

Does this tell me whether a signature is valid?

No, and it never will. HerePDF reads what the signing software wrote into the file (a name, a reason, a time, a format) and checks whether the signed part reaches the end of the file. It does not check the signature itself, the certificate behind it, whether that certificate is trusted, or whether the content inside the signed part was changed. For a verdict, open the file in Adobe Acrobat or ask the service that signed it.

Can I trust the name and time shown?

Not on their own. They are text that the signing software put in the file, and anyone's software can write any name or time there. The real identity is in the certificate, which this tool does not read. The time is the signer's own computer clock unless the file carries a separate trusted timestamp.

What does "changes were saved after this signature" mean?

The file was saved again after it was signed, and the new data sits after the signed part. That is ordinary when a second person signs next or someone fills in a form field. It is also how a signed file can be altered. This tool counts the later saves but cannot tell you which kind they were.

Does a signature that reaches the end of the file mean nothing changed?

It means nothing was added after it. The signed bytes themselves could still have been altered or forged, and only a check of the cryptography would show that.

Is the drawn signature from the Sign tool a digital signature?

No. The Sign tool draws an image of a signature onto the page, which is a visual signature. A digital signature is a cryptographic block with a certificate behind it, and that is what this tool looks for. A file with only a drawn signature shows no digital signatures here.

Does the file get uploaded?

No. HerePDF reads the signatures with PDF.js inside your browser, and the file never leaves your device. Nothing is changed or saved either: this tool only reads.