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PDF is one of the most popular formats for documents but they can be a pain if you accidentally lock your PDF or if you receive a locked pdf files from somebody. The locking can prevent you from editing, merging and even printing the document. PDFUnlock! is a simple tool that unlocks any PDF for you.
Simply upload the locked PDF and click unlock!. The tool will then unlock the document and download it to your computer. Note that you cannot recover lost passwords. PDFUnlock just removes the password protection so the PDF is unlocked.
The maximum file size you can upload is 10 MB. The documents can sometimes lose a little bit of quality but nothing significant. PDFUnlock also doesn’t remove any encryptions such as DRM, it only cracks the password protection settings.
Update from the developer:
PDFUnlock! also doesn’t remove any encryptions such as DRM
“third party” or “non-standard” encryptions would be a more correct statement.
Many people are unaware of the two different types of passwords in the PDF standard. Explaining those shortly might save us both a few disappointed readers/visitors/comments.
The “owner password” is used to impose the “locking” restrictions you already mention in your article. However, the way the PDF standard works, these restrictions can be circumvented in a matter of seconds. This is what PDFUnlock! does.
The “user password”, however, is used to prevent anyone who does not know the password from opening the file. Unlocking files that are protected with an unknown user password can only be done by brute force. With very few exceptions it is a very time consuming process, and cannot be provided as a quick upload/download type of web service such as PDFUnlock!
That said, if the uploader knows the user password, but doesn’t have a PDF editor (such as Acrobat) he/she can remove it with, PDFUnlock! can be used to remove it if the password is provided (in these cases, it is asked for after the file has been uploaded).
- Unlock PDF documents online.
- Upload files up to 10 MB.
- Enables PDF for editing, merging and printing.
- No registration required.
- Similar tools: Unlock-PDF or Freeware PDF Unlocker (desktop app).
Visit PDFUnlock @ www.PDFUnlock.com