Display command-line invocation help.

Display the current version of qpdf.

Show detailed copyright information.

Show a list of available crypto providers, each on a line by itself. The default provider is always listed first. See Section 2.3, “Crypto Providers” for more information about crypto providers.

Output a completion command you can eval to enable shell completion from bash.

Output a completion command you can eval to enable shell completion from zsh.

Specifies a password for accessing encrypted files. Note that you can use @filename or @- as described above to put the password in a file or pass it via standard input so you can avoid specifying it on the command line.

Silently exit with status 0 if the file is encrypted or status 2 if the file is not encrypted. This is useful for shell scripts. Other options are ignored if this is given. This option is mutually exclusive with --requires-password. Both this option and --requires-password exit with status 2 for non-encrypted files.

Silently exit with status 0 if a password (other than as supplied) is required. Exit with status 2 if the file is not encrypted. Exit with status 3 if the file is encrypted but requires no password or the correct password has been supplied. This is useful for shell scripts. Note that any supplied password is used when opening the file. When used with a --password option, this option can be used to check the correctness of the password. In that case, an exit status of 3 means the file works with the supplied password. This option is mutually exclusive with --is-encrypted. Both this option and --is-encrypted exit with status 2 for non-encrypted files.

Increase verbosity of output. For now, this just prints some indication of any file that it creates.

Indicate progress while writing files.

Suppress writing of warnings to stderr. If warnings were detected and suppressed, qpdf will still exit with exit code 3. See also --warning-exit-0.

If warnings are found but no errors, exit with exit code 0 instead 3. When combined with --no-warn, the effect is for qpdf to completely ignore warnings.

Causes generation of a linearized (web-optimized) output file.

If specified, the output file name should be omitted. This option tells qpdf to replace the input file with the output. It does this by writing to infilename.~qpdf-temp# and, when done, overwriting the input file with the temporary file. If there were any warnings, the original input is saved as infilename.~qpdf-orig.

Encrypt the file using the same encryption parameters, including user and owner password, as the specified file. Use --encryption-file-password to specify a password if one is needed to open this file. Note that copying the encryption parameters from a file also copies the first half of /ID from the file since this is part of the encryption parameters.

If the file specified with --copy-encryption requires a password, specify the password using this option. Note that only one of the user or owner password is required. Both passwords will be preserved since QPDF does not distinguish between the two passwords. It is possible to preserve encryption parameters, including the owner password, from a file even if you don't know the file's owner password.

Causes generation an encrypted output file. Please see Section 3.4, “Encryption Options” for details on how to specify encryption parameters.

Removes any encryption on the file. A password must be supplied if the file is password protected.

Overrides the usual computation/retrieval of the PDF file's encryption key from user/owner password with an explicit specification of the encryption key. When this option is specified, the argument to the --password option is interpreted as a hexadecimal-encoded key value. This only applies to the password used to open the main input file. It does not apply to other files opened by --pages or other options or to files being written.

Most users will never have a need for this option, and no standard viewers support this mode of operation, but it can be useful for forensic or investigatory purposes. For example, if a PDF file is encrypted with an unknown password, a brute-force attack using the key directly is sometimes more efficient than one using the password. Also, if a file is heavily damaged, it may be possible to derive the encryption key and recover parts of the file using it directly. To expose the encryption key used by an encrypted file that you can open normally, use the --show-encryption-key option.

Ordinarily, qpdf attempts to automatically compensate for passwords specified in the wrong character encoding. This option suppresses that behavior. Under normal conditions, there are no reasons to use this option. See Section 3.10, “Unicode Passwords” for a discussion

This option can be used to fine-tune how qpdf interprets Unicode (non-ASCII) password strings passed on the command line. With the exception of the hex-bytes mode, these only apply to passwords provided when encrypting files. The hex-bytes mode also applies to passwords specified for reading files. For additional discussion of the supported password modes and when you might want to use them, see Section 3.10, “Unicode Passwords”. The following modes are supported:

Apply rotation to specified pages. The page-range portion of the option value has the same format as page ranges in Section 3.5, “Page Selection Options”. If the page range is omitted, the rotation is applied to all pages. The angle portion of the parameter may be either 90, 180, or 270. If preceded by + or -, the angle is added to or subtracted from the specified pages' original rotations. This is almost always what you want. Otherwise the pages' rotations are set to the exact value, which may cause the appearances of the pages to be inconsistent, especially for scans. For example, the command qpdf in.pdf out.pdf --rotate=+90:2,4,6 --rotate=180:7-8 would rotate pages 2, 4, and 6 90 degrees clockwise from their original rotation and force the rotation of pages 7 through 9 to 180 degrees regardless of their original rotation, and the command qpdf in.pdf out.pdf --rotate=+180 would rotate all pages by 180 degrees.

This option controls whether qpdf keeps individual files open while merging. Prior to version 8.1.0, qpdf always kept all files open, but this meant that the number of files that could be merged was limited by the operating system's open file limit. Version 8.1.0 opened files as they were referenced and closed them after each read, but this caused a major performance impact. Version 8.2.0 optimized the performance but did so in a way that, for local file systems, there was a small but unavoidable performance hit, but for networked file systems, the performance impact could be very high. Starting with version 8.2.1, the default behavior is that files are kept open if no more than 200 files are specified, but that the behavior can be explicitly overridden with the --keep-files-open flag. If you are merging more than 200 files but less than the operating system's max open files limit, you may want to use --keep-files-open=y, especially if working over a networked file system. If you are using a local file system where the overhead is low and you might sometimes merge more than the OS limit's number of files from a script and are not worried about a few seconds additional processing time, you may want to specify --keep-files-open=n. The threshold for switching may be changed from the default 200 with the --keep-files-open-threshold option.

If specified, overrides the default value of 200 used as the threshold for qpdf deciding whether or not to keep files open. See --keep-files-open for details.

Select specific pages from one or more input files. See Section 3.5, “Page Selection Options” for details on how to do page selection (splitting and merging).

When specified, collate rather than concatenate pages from files specified with --pages. See Section 3.5, “Page Selection Options” for additional details.

For each page that is rotated using the /Rotate key in the page's dictionary, remove the /Rotate key and implement the identical rotation semantics by modifying the page's contents. This option can be useful to prepare files for buggy PDF applications that don't properly handle rotated pages.

Write each group of n pages to a separate output file. If n is not specified, create single pages. Output file names are generated as follows:

Page ranges are a single number in the case of single-page groups or two numbers separated by a dash otherwise. For example, if infile.pdf has 12 pages

Note that outlines, threads, and other global features of the original PDF file are not preserved. For each page of output, this option creates an empty PDF and copies a single page from the output into it. If you require the global data, you will have to run qpdf with the --pages option once for each file. Using --split-pages is much faster if you don't require the global data.

Overlay pages from another file onto the output pages. See Section 3.6, “Overlay and Underlay Options” for details on overlay/underlay.

Overlay pages from another file onto the output pages. See Section 3.6, “Overlay and Underlay Options” for details on overlay/underlay.

Determines whether or not to allow printing.

Determines whether or not to allow document modification.

Determines whether or not to allow text/image extraction.

Determines whether or not to allow comments and form fill-in and signing.

Determines whether or not to allow accessibility to visually impaired. The qpdf library disregards this field when AES is used or when 256-bit encryption is used. You should really never disable accessibility, but qpdf lets you do it in case you need to configure a file this way for testing purposes. The PDF spec says that conforming readers should disregard this permission and always allow accessibility.

Determines whether or not to allow text/graphic extraction.

Determines whether document assembly (rotation and reordering of pages) is allowed.

Determines whether modifying annotations is allowed. This includes adding comments and filling in form fields. Also allows editing of form fields if --modify-other=y is given.

Determines whether filling form fields is allowed.

Allow all document editing except those controlled separately by the --assemble, --annotate, and --form options.

Controls printing access. print-opt may be one of the following:

Controls modify access. This way of controlling modify access has less granularity than new options added in qpdf 8.4. modify-opt may be one of the following:

Using the --modify option does not allow you to create certain combinations of permissions such as allowing form filling but not allowing document assembly. Starting with qpdf 8.4, you can either just use the other options to control fields individually, or you can use something like --modify=form --assembly=n to fine tune.

If specified, any metadata stream in the document will be left unencrypted even if the rest of the document is encrypted. This also forces the PDF version to be at least 1.5.

If --use-aes=y is specified, AES encryption will be used instead of RC4 encryption. This forces the PDF version to be at least 1.6.

Use of this option forces the /V and /R parameters in the document's encryption dictionary to be set to the value 4. As qpdf will automatically do this when required, there is no reason to ever use this option. It exists primarily for use in testing qpdf itself. This option also forces the PDF version to be at least 1.5.

This option is not available with 256-bit keys. AES is always used with 256-bit encryption keys.

This option is not available with 256 keys.

If specified, qpdf sets the minimum version to 1.7 at extension level 3 and writes the deprecated encryption format used by Acrobat version IX. This option should not be used in practice to generate PDF files that will be in general use, but it can be useful to generate files if you are trying to test proper support in another application for PDF files encrypted in this way.