Verify a PDF signature
Find out whether a signed PDF is still exactly as it was signed, and who signed it and when.
- Detects changes after signing
- Signer, time, reason and certificate
- Every signature in the file
- Never uploaded
Click on the page to place your text.
How to verify a PDF signature
- Step 1Add the signed PDFDrop the document you received.
- Step 2Check signaturesEach signature is checked on your device.
- Step 3Read the reportSee the result on screen, or keep the report file.
Questions
Is it free to verify a PDF signature?
Yes. It is free with no sign-up and no watermark. The free plan covers up to 50 tasks a day; Pro removes every limit.
Do you upload my files?
No. The tool runs inside your browser using WebAssembly. Your file never leaves your device, and it still works with Wi-Fi turned off.
Does it work on my phone?
Yes. It works in Chrome, Safari, Edge and Firefox on Android, iPhone, Windows, Mac and Linux.
What does "changed after signing" mean?
Content was added to the file after it was signed, such as another signature, a form entry or a comment. The signed part is intact; open the file in Adobe Reader to see what was added.
Does it check whether the signer is trusted?
It shows who issued the certificate, but it does not check trust lists or revocation, which needs online checks. Adobe Acrobat Reader does that.