Frequently Asked Questions

Is PDFEncrypt really free?

Yes, PDFEncrypt is completely free and is released under the AGPL.  Donations are greatly appreciated if you find this app to be helpful.

How do I use PDFEncrypt?


  • Select an unencrypted PDF file that you want to encrypt.
  • A destination (encrypted) filename is automatically generated.  Leave as-is or change to the desired file.
  • Enter the desired password or click Generate to generate an alphanumeric password.
  • Click Encrypt
  • The PDF file will be encrypted and saved in the destination location.
  • Alternatively, you can automate PDFEncrypt using command-line arguments.


It says I need .net Framework. What is this?

The Microsoft .net Framework is a set of supporting software libraries that PDFEncrypt needs to run.  If the framework is not installed automatically during PDFEncrypt setup, you can download and install from Microsoft by clicking here: Download .net Framework 4.7.2 installer.  Simply download and run the installer and follow the prompts to install.  Then launch PDFEncrypt and start creating encrypted PDF files!

What do the settings do?

PDFEncrypt provides several encryption options as well as program features. Click the “Settings…” button to configure the app. 

    • Confirm password – Requires the user to re-enter the password to confirm it before encryption is performed.
    • Encrypt metadata – PDF files contain metadata about the document.  This setting allows you to encrypt or leave this data unencrypted.
    • Permissions:
      • Allow printing (hi-res) – users will be permitted to print the document in full resolution
      • Allow printing (low-res) – users will be permitted to print the document, but only at low resolution (i.e. 150dpi)
      • Allow modifying – allow users to modify the document
      • Allow modify annotations – users will be permitted to modify annotations
      • Allow copying – users will be permitted to highlight and copy text/graphics from the document
      • Allow form fill – users will be permitted to fill existing forms in the document
      • Allow assembly – users will be permitted to assemble the document
      • Allow screenreaders – screen reader software will be permitted to read the document
    • Algorithm – select an encryption algorithm to achieve the desired compatibility with Adobe Reader versions.
    • After successful encryption:
      • Show destination file in Explorer – Windows Explorer will be opened with the encrypted file selected
      • Open destination file – attempt to open the encrypted document with the default PDF viewer application (if any)
      • Close PDFEncrypt – close the PDFEncrypt software
      • Run a program – run the specified executable program and pass the encrypted filename as the first parameter.  Specify command-line arguments in the Arguments box.
What encryption algorithms are available?

PDFEncrypt supports AES-256, AES-128, RC4-128, or RC4-40 encryption.  AES-256 is recommended, but is only supported by Adobe Reader 8 or above.  If you must support older readers, select from the other encryption ciphers, or request that users update their Reader software.

Does PDFEncrypt support Silent Installation?

Yes: run the installer with the /silent or /verysilent switch.

I found a bug, have a feature suggestion, or need help. What to do?

Contact us using the “Ask a Question” button below.

Does my PDF file get transferred across the internet to be encrypted?

No.  Your file stays on your local PC. The encryption is performed by a PDF software library running on your computer (powered by iTextPDF). 

Full disclosure: iTextPDF is a third-party library not written by me.  The makers of iTextPDF are not a sponsor of PDFEncrypt and are in no way affiliated with this project.

Because of the restrictive license of the iTextPDF library, we have plans to move to a more “open” PDF encryption library for the next version of PDFEncrypt.

What encryption library does PDFEncrypt use?

PDFEncrypt uses the open-source iTextPDF library to perform PDF manipulation, which depends on the open-source BouncyCastle.crypto.dll crypto library.

Does PDFEncrypt support command-line arguments?
Yes, PDFEncrypt supports the following command-line arguments:

-i [input filename] or --input [input filename]

-o [output filename] or --output [output filename]

--user_pass [user password]

--owner_pass [owner password]

--run - immediately execute the Encrypt function on startup (don't wait for the user to click the Encrypt button).

Please note the double-dash in front of “input”, “output”, “user_pass”, “owner_pass”, and “run”.  Any multiple-character command-line argument must be preceded with a double-dash instead of a single dash.  The website does not show this clearly on some screens.

Does PDFEncrypt handle large files?

PDFEncrypt successfully processes PDF files over 100MB, containing multiple graphics and text.

I disabled permissions: printing/modification/copying/assembly. Why are these actions still permitted?

The PDF viewer application gets to choose whether to enforce these permissions.  If you are using Adobe Reader, these permissions will be enforced. Other PDF viewers, such as the viewer built in to the Firefox browser, ignore these permissions and allow the user full control once the password to decrypt the file has been entered.

The contents of the PDF file are still secure* and unreadable (encrypted) until the password is entered, no matter which viewer is being used to open the file.

Please see this blog post for a more detailed explanation.

* To ensure maximum security, please be sure to select the AES-256 encryption algorithm.

Does PDFEncrypt provide DRM (digital rights management) or allow me to choose who can open my PDF or when it can be opened (expiration)?

No. PDFEncrypt simply allows you to encrypt the entire PDF document using a single password.  This allows you to securely email or otherwise transfer the file across insecure media. 

Anyone who has the password can open the PDF file at any time, as many times as they want, and they can also share the PDF file with others (as long as they share the password also). 

See this blog post about PDFEncrypt and DRM solutions.

How do I remove the password from an encrypted PDF file?

Without expensive software like Adobe Acrobat, you can’t *directly* remove the password.  But you *can* open the password-protected file using the password, then print it using the Microsoft PDF Printer (Windows 10 or above) or another PDF printer, to create a new PDF file without a password.

What are the system requirements?

Windows 7 or newer – .net Framework 4.7.2

I forgot the password I used to encrypt a file. What now?

If you forgot the password, the PDF file can’t be retrieved.  You should always save a backup copy of the unencrypted document.  That’s why PDFEncrypt won’t allow you to overwrite your existing document with the encrypted version.

Does PDFEncrypt contain viruses, spyware, ransomware, or adware?

NO. The official binaries downloaded from PDFEncrypt.net do not contain malware or adware. The installer is generated with Inno Setup and contains the executable, dll’s, and supporting files needed to run PDFEncrypt, as well as a .net Framework installer. You can also download the source code and build it on your own computer if you have concerns about third-party software.

How can I verify the authenticity of PDFEncrypt downloads?

In Windows 10 or above, you can use PowerShell’s command “Get-FileHash” to calculate the SHA1-sum for your downloaded files.

  1. Open PowerShell (click Start -> type “PowerShell” and click on Windows PowerShell)
  2. Type the command (don’t type the quotes): “Get-FileHash -algorithm sha1 [filename]”
    (Replace [filename] with the path and name of the file you downloaded.)
  3. Check that the returned SHA1 hash matches the hash given on the PDFEncrypt.net website for the file you’re downloading. If they match, the file is authentic! If not, the file was changed in some way. Delete the download and retry.

-> Example screenshot

(The SHA1 hash will be different based on which file you download! Also, this hash will change each time we release a new version of the software.)

Remember: Only download the app directly from the official website https://pdfencrypt.net or from the Microsoft Store using this link.

Can I advertise on this site?

PDFEncrypt.net receives many visits each month from a worldwide audience of real people, making it an ideal spot to advertise.

If you are interested in displaying a tasteful ad for a useful product or service on this site, please contact me with a proposal.

However, please keep in mind that I will never bundle any type of adware or other third party software with the PDFEncrypt application or installer.

Who is behind PDFEncrypt?

I am Ryan Griggs, developer and maintainer of PDFEncrypt.  I am a software developer and IT professional located in the eastern United States. I created PDFEncrypt in response to a need expressed by a client.  When unable to find any free or inexpensive software to meet the need, I built this app and released it as open source software.

Consider A Donation

PDFEncrypt is a completely free, open-source application dedicated to providing document security. This application and site are maintained by a single developer, Ryan Griggs, at his own personal expense.

If PDFEncrypt is helpful to you, please consider donating to help keep it going.

Thank you very much!