Programs to unlock PDF

You have to print a file in PDF format but it is not possible because when trying to do this you are asked to enter a password? Some time ago you protected a PDF with a password but now you can no longer view it because you do not remember the relative access key? Don’t despair! You can cope with such situations by resorting to the use of some tools specifically designed for the purpose, those that you find indicated in this guide of mine.

Position yourself, therefore, nice and comfortable, take a few free minutes just for you and immediately begin to concentrate on reading what is reported below, to discover the best programs to unlock PDFs on the square. I already anticipate that there are both for Windows and for macOS and that there are also resources that can be used directly via the Web, without having to install any particular plugin for the browser and without downloading anything on the PC, except for the final file, of course.

For completeness of information, I will also show you some apps for Android smartphones and tablets and for iPhone and iPad that you can use to unlock your documents on the go, without having to go through your PC. Now, however, just chat and let’s move on. Good luck for everything!

Index

• Preliminary information
• Programs to unlock secure PDFs for free
  • QPDF (Windows / macOS / Linux)
  • PDFCrack (Windows / macOS)
• Programs to unblock PDFs online
  • Online2PDF
  • PDF2Go
• App to unlock PDF

Preliminary information

Before getting to the heart of the tutorial, going to indicate which are the best programs to unlock PDF, it is my duty to provide you with some preliminary information about it.

In case you are not already aware of it, I inform you that there are two different types of passwords that can be applied to PDFs to preserve documents. There is the owner password, which protects the files against printing and/or modification, and there is the user password which, on the other hand, prevents the PDF from being opened.

The owner password can be bypassed quite simply and usually only a few seconds are enough, while the user password is much more difficult to bypass, as it is necessary to carry out a “brute force” attack on the document, trying all possible combinations of characters until you find the correct one, an operation that can take several hours, or even days.

Programs to unlock secure PDFs for free

Having made the necessary clarifications above, let’s get to the real core of the topic and let’s find out which are the best programs to unlock PDF currently on the square. Below, therefore, you will find reported what I believe to be the most interesting free resources for Windows, macOS and Linux.

QPDF (Windows / macOS / Linux)

QPDF  is a free program, of an open-source nature and running on Windows, macOS and Linux that allows you to bypass the protection applied to PDFs by intervening on the owner password. It is not difficult to use, but it should be noted that it does not have a graphical interface, so it can only be used from the command line.

To download the software on your PC, if you are using Windows, go to the QPDF download page on the SourceForge website and click on the Download Latest Version button located at the top left.

When the download is complete, extract the resulting ZIP archive to a desired location and start QPDF via the Command Prompt, directing it to the folder containing the program. To do this, proceed as follows: hold down the Shift key on the PC keyboard, right-click on the bin folder in the folder where you extracted QPDF and, from the menu that appears, select the Open command window here item.

Once the Command Prompt window appears on the screen, enter the string qpdf –decrypt input.pdf output.pdf(instead of input.pdf and output.pdf you must enter the full path of the PDF to be unlocked and the output file to be obtained; you can get the full path of a file by dragging it to command line) and press the Enter key. After doing these steps, you will get an unlocked version of the PDF in the folder chosen for the output file.

If you are using macOS, however, to download and install the program you have to contact  Homebrew, a free and open source package manager that allows you to install various types of software using the  Terminal. So, first of all open the Terminal, selecting the relative icon (the one with the black window and the line of code ) that you find in the Other folder of the Launchpad.

Once the Terminal window appears on the desktop, to install Homebrew, enter the command /usr/bin/ruby -e “$(curl -fsSL https://raw.githubusercontent.com/Homebrew/install/master/install)”, followed by pressing the Enter key on the Mac keyboard and entering the computer administration password . Then, to install QPDF, enter the command brew install qpdf, always followed by pressing the Enter key.

After completing the installation procedure, enter the command in the Terminal window qpdf –decrypt input.pdf output.pdf(instead of input.pdf and output.pdf you must enter the paths of the input and output files; you can get the full path of a file simply by dragging it to the command line) and press the Enter key to get a password-free version of the PDF. Et voila!

PDFCrack (Windows / macOS)

Another PDF unlocker that I want to invite you to consider is PDFCrack. It is able to act on documents protected with a user password, is available for both Windows and macOS and also does not have a graphical interface, so it must always be used from the command line.

To download the software to your PC, if you are using  Windows, visit its website and click the Download link ( pdfcrack-xx.zip , xxk) located on the right.

When the download is complete, open the resulting ZIP archive and extract the contents in a folder of your choice. Now, call up the Command Prompt by clicking on the Start button (the one with the Windows flag ) located at the bottom left of the taskbar, typing “prompt”  in the search field displayed and selecting the relevant link from the menu that opens. opens.

Once the Command Prompt window appears on the desktop, type the command CD “[cartella PDFCrack]”(instead of [cartella PDFCrack]you have to enter the full path to the folder where you extracted PDFCrack) and press the Enter key on your computer keyboard. Next, enter the command pdf crack “file.pdf”(instead of file.pdf you have to enter the full path and name of the file to decrypt) and press the Enter key again.

Once you have carried out the above steps, PDFCrack will start to attack the PDF to identify the password and when it has found it you will be shown the written found user password, together with the access key for the document.

If you are using macOS, on the other hand, to download PDFCrack visit the download page on the SourceForge website and click on the Download Latest Version button at the top.

When the download is complete, open the tar.gz archive obtained and extract the contents in a folder of your choice. Next, call the Terminal, selecting the icon (the one with the black window and the line of code ) that you find in the Other folder of the Launchpad, type the command cd [cartella PDFCrack](instead of [cartella PDFCrack]you must enter the full path of the folder where you extracted PDFCrack) and press the Enter key on your keyboard. Then enter the command make f Makefile, always followed by pressing the Enter key.

After performing the above steps, open a new Terminal window, enter the command [cartella PDFCrack]/pdfcrack -u “file.pdf”(instead of [cartella PDFCrack]you have to type the full path of the folder where you extracted PDFCrack and instead of file.pdf you have to enter the full path and name of the file to decrypt) and press the Enter key to find out the PDF password.

Programs to unblock PDFs online

As I told you at the beginning of the guide, there are also programs to unlock PDFs that work directly and conveniently online, without having to download and install anything, by acting directly from the browser window (any). If this interests you, below you will find those that I believe represent the best in the category.

Online2PDF

The first online service useful for bypassing the password applied to PDFs that I invite you to try is  Online2PDF. It is free, requires no registration and, in addition to fulfilling the purpose in question, allows you to edit and convert PDF files, even by acting in batches. It should be noted that, as regards the unlock issue, it is able to act both on files protected against printing and modification and on those protected from unauthorized access, but in this second case you need to know the password in order to create a copy ” free “of the document.

Other things to keep in mind are that the service does not allow you to upload more than 20 files at a time, that the maximum size allowed for individual files is 100 MB, and that the total size must not exceed 150 MB. As far as privacy is concerned, Online2PDF removes the files uploaded to its servers within a few hours of uploading.

To use the service, visit its home page and drag the documents to be unlocked onto the dotted rectangle located in the center. Alternatively, click on the Select files button and “manually” select the PDFs you want to act on.

Once the upload procedure is complete, if you are trying to unlock PDFs protected with an owner password, click directly on the Convert button at the bottom, wait for an “unprotected” copy of the files to be created and the download to start automatically. If the download does not start automatically, you can force it yourself by selecting the Switch to manual download link that you see appearing.

If, on the other hand, the ones you want to unlock are PDFs protected with a user password, before proceeding with the download as I explained above, you will have to click on the black button with the padlock that appeared next to the name of each document following the upload and type the relevant password in the text field.

PDF2Go

Another online service you can consider appealing to is  PDF2GO. It is at no cost, easy to use and provides users with various tools to act on PDFs, converting them, compressing them, merging them, etc., even by operating on multiple elements simultaneously. Obviously, it also allows you to unlock this type of documents, acting on both the owner password and the user password, but in this second case the entry of the relative access key is required first, to create freely accessible copies of the files.

The only thing to be aware of is that no files larger than 50MB can be uploaded. To increase this limit, you need to create a free account to use the service or you need to switch to the paid version of the same (with costs starting from € 5.50 / month), which also allows you to enjoy other benefits. With regard to privacy, however, this is protected as all files uploaded to the service are deleted after 24 hours.

To use PDF2GO, first connect to the service’s website and drag the PDFs you want to act on into the browser window. Alternatively, you can select the documents by hand by clicking the Choose a file button. If your files are on one of the supported cloud storage services ( Google Drive and Dropbox ), you can also pick them up from there by clicking on its icon. You can also upload files from any other location online by selecting the Enter URL link and typing the relevant link.

Once uploaded, click on the Start button at the bottom, wait for the files to be processed and, if protected against printing and modification, the “free” PDF download will start automatically. If the download doesn’t start by itself, you can force it by pressing the Download button.

On the other hand, if the uploaded PDFs are protected with a user password, before being able to download them as I have just indicated, you will have to type the relative password in the Enter the password field which, following the upload, you will see appear at the bottom next to the name of each document, and then you will need to click the Set Password button.

App to unlock PDF

You don’t have a computer at hand and would you like me to suggest programs to unlock PDFs for Android and iOS? I’ll settle you immediately! In fact, below you will find a list of applications for smartphones and tablets that you can consider using to act directly on the move. Try them now!

• iLovePDF( Android / iOS / iPadOS ) – is the application of a renowned online service that allows you to make various types of changes to PDFs. It also includes a tool to remove the password applied to the files in question, but in the specific case of protection against opening it must first be typed in order to create an unsecured copy. It’s free, but offers in-app purchases (at a cost of € 5.99 / month or € 48.99 / year) to remove advertisements and take advantage of other extra features.
• PDF Tools( Android ) – free app for Android devices only that allows you to work on PDF files in various ways: by joining them, dividing them, extracting specific pages, etc. Obviously, it also allows you to unlock the protected ones, both with the owner password and with the user password (in the latter case you must first type it in order to create a copy of the file that is freely accessible).
• PDF Unlocker( iOS / iPadOS ) – app that works only on iPhone and iPad which, as easily understood by the name itself, allows you to unlock PDFs protected against printing, editing and opening. In the specific case of the files to which the user password is applied, however, the relative access key must first be provided, in order to generally have a free copy.