How to set password for pdf files?
I need to password protect my PDF file(s), because I am going to send them through email and I want anyone who would view my PDF file(s) to be prompted for a password.
How can I add a password to a PDF in Linux Mint 17.1?
You can use the program
pdftk to set both the owner and/or user password
pdftk input.pdf output output.pdf owner_pw xyz user_pw abc
user_pw are the commands to add the passwords
abc respectively (you can also specify one or the other but the
user_pw is necessary in order to prohibit opening).
You might also want to ensure that encryption strength is 128 bits by adding (though currently 128 bits is default):
If you cannot run
pdftk as it is no longer in every distro, you can try
qpdf --help gives information on the syntax. Using the same "values" as for
qpdf --encrypt abc xyz 256 -- input.pdf output.pdf
The pdftk toolkit allows for this type of functionality on Linux.
- open your Ubuntu Terminal
- install pdftk by using this command:
sudo apt-get install pdftk
- make sure pdftk is now installed by writing this on the terminal:
pdftk. You will see a bunch of pdftk command instructions if it already installed
- simply use this command to add a password to your existing pdf document:
pdftk <source>.pdf output <destination>.pdf userpw <password>
pdftk Mydocs.pdf output Mydocs_pass.pdf userpw secretword
You can also export an encrypted PDF file from Libre Office (File -> Export as PDF -> Security tab -> Set Passwords -> Set open password), if necessary importing your existing PDF into the Draw program first.
pdftk depends on old libraries, and so is no longer in the repos of Fedora / CentOS. As a replacement, I prefer qpdf
qpdf --encrypt [readpass] [ownerpass] 256 -- [infile].pdf [outfile].pdf
On Fedora, you can use pdf-stapler to set a password for a PDF file, and also perform other pdftk-like operations.
Example to set the user password (the one required for opening the file):
pdf-stapler -u QRNFFtVXA-8PqF cat input_file.pdf output_file.pdf
This is the password you think of most likely about setting a password to a PDF file.
In case you want to set the owner password (the one that defines permissions like printing, commenting, ect.), use the
Using tools from the Poppler Toolset (from a package like
poppler-tools), you can achieve this with a combination of
pdftops in.pdf out.ps
ps2pdf -sUserPassword=XXXXX -sOwnerPassword=YYYYY out.ps out.pdf
Note that to set a User (view) password, you must set an Owner (edit) password.