Xceed Zip for x64

Flexible, and unbelievably reliable and mature, with a 20-year track record. Updated and improved often, and backed by a responsive support and development team whose sole ambition is your complete satisfaction.

  • High-performance
  • Supports the latest zip file format standards
  • The richest feature set with 115 capabilities
What’s New?

The only Zip library compatible with all the latest updates to the Zip archive format, including UTF-8 to support all characters in filenames, and LZMA for WinZip 12+ compatibility.

An easy to use ActiveX/COM data compression library built for the x86-64 architecture. You name the feature, it does it. Zip, unzip, updating, converting, disk and memory streaming, AES encryption, no 4GB or file limit, various compression algorithms, filtering, split/spanned/self-extracting zip files, and much more.

Technically superior

The library is a fully self-contained DLL, written with ATL 3.0 and with no external dependencies, STA/MTA multi-threaded apartment models, Unicode file and I/O calls, and more. Use it as an ActiveX/COM control, or access it as a standard 64-bit DLL through its exported API.

Advanced capabilities include non-blocking methods for background operation, wildcards that work even for folder names, renaming files in a zip file without unzipping then rezipping, etc.


Updated and improved for over 20 years, used in applications everywhere, you can trust it to create robust applications that execute error-free with any kind of input data.

Appreciated by top developers

“We’ve been using Xceed Zip for some time now, originally for an archiving utility, but now for various other utilities. It has met all our requirements! I’ve found it easy to use, and the help contains good examples, which is pretty rare to find these days.”
Robert Copeland, Talgentra Ltd (Auckland, New Zealand)
“I use Xceed Zip for my projects. I love this component and it does save me lots of unnecessary hassles. On top of the high quality components that Xceed provides, I also had chances to work with their technical support team. They are extremely nice people with solid knowledge and they were able to answer all of my questions. I believe that’s one of Xceed’s strongest selling point besides the software itself and I’m confident that I will continue to count on Xceed’s team for my future needs.”
Michael Wu, CSC @ BHP Billiton (Houston, Texas, United States)
“Our program has been running for something like four years without any problems, delivering 4k packets of compressed information to up to 100 users at a time using Xceed Zip and uncompressing them for display in .25 of a second! In all that time we have not had one data error thanks to your superb compression software – and of course my superb use of it!”
Barry Harkcom, I.T.Consultant, Jones Lang LaSalle (United Kingdom)


ActiveX/DLL technology

  • Built for the x86-64 processor architecture. A version for the IA-64 processor architecture is also available on request.
  • A single fully self-contained COM object and ActiveX control written with ATL 3.0.
  • Requires no external compression DLLs, MFC DLLs, or other runtime libraries.
  • Both single-threaded (STA) and multi-threaded apartment (MTA) model design.

  • Instantiate the component dynamically without putting it on a form.
  • Supports multiple instances running simultaneously.
  • Supports both Unicode and ANSI in one single control. The library automatically uses Unicode API calls for best performance where available.
  • ActiveX control interface has all constants, enumerations, and types built-in. Code completion, property categories, help strings, and context-sensitive F1-help fully supported.
  • Works with all 32-bit development environments that can use ActiveX controls, including VB, VC++, Delphi, C++ Builder, VFP, Office, PB, VO, Web scripting languages, ASP, and DCOM projects.
  • Also compatible with VB.NET and C#. For developers that require 100% managed code, check out Xceed Zip for .NET, our fully object-oriented Zip, compression and FileSystem class library.

Compression & Zip file technology

  • Supports WinZip 9.0 (and up) compatible AES strong encryption.
  • Fast, low memory usage compression engine.
  • 100% compatible with the PKZIP 2.04g format.
  • 100% compatible with the PKZIP 4.5 format.
  • Supports the Zip64 zip file format allowing the creation of Zip files of practically unlimited size (no 4 GB limit).

  • Supports the BZip2 (BWT) compression method for 15% to 20% better compression than Deflate on many popular file types, especially XML data.
  • The only library to provide WinZip 12 compatibility, supporting the LZMA algorithm for improved compression in certain situations. Note: Zip files using WinZip 12’s special JPEG recompression feature are not supported.
  • UTF-8 character encoding in headers for improved support of international characters in filenames and comments is provided.
  • Supports the Deflate64TM compression method, an industry standard improvement to regular Deflate.
  • Zip files can contain any number of files (no 65535 file limit).
  • Regular, spanned, and self-extracting zip files created by Xceed Zip can be used by any of today’s existing unzipping applications, and vice-versa.
  • Stores and retrieves the latest zip file format extensions, allowing Unicode filenames and NT file attributes, extra time stamps, and security permissions to be stored in the zip file.
  • No need to repair corrupted zip files. Xceed Zip automatically tries to recover from errors and reports any inconsistencies found in the zip file while unzipping.

Major operations

  • Zip files or memory buffers into new or existing zip files.
  • Unzip files to disk or directly to memory.
  • Compress and decompress strings or buffers completely in memory.
  • All compression and decompression modes support streaming and encryption.
  • Create fully customizable self-extracting zip files (see section below for features)

  • Convert any type of zip file (regular, spanned, multi-part, self-extracting, or spanned self-extracting) into any other type of zip file.
  • Reads and writes zip files that span multiple disks.
  • Reads and writes multi-part zip files directly to hard drive.
  • Update one zip file from another one’s contents or merge two zip files together.
  • Optional background processing so your code can continue execution while Xceed Zip is working.

Application-component interactivity

  • All operations can be aborted at any time.
  • Provides status report events on a file-by-file basis as well as on the entire operation being performed, with percentages, byte, and file counts. Easily add any kind of progress bar to your apps.
  • Events are triggered whenever a file is being zipped, unzipped, updated, deleted, etc.
  • Notifies your application when and why a specific file cannot be processed.

  • Notifies your application when a file being zipped or unzipped is about to overwrite an existing file. Your application can then choose to overwrite it or skip it. You can also rename files.
  • Provides complete file information for the file currently being processed.
  • Your application receives info such as a file’s achieved compression ratio, compressed size, and other info as it becomes available.
  • Informs your application that it should prompt the user to insert a specific disk when reading or writing zip files that span multiple disks.
  • Many events have modifiable parameters to allow your application to change file parameters or specifications as the files are being zipped, unzipped, converted, etc.
  • Unused events can be prevented from being triggered for increased performance.
  • Provide feedback to the user when the temporary zip file is being copied to its final destination.
  • Provide feedback to the user when the zip file’s central directory is being written.

Zip file manipulation functionality

  • Obtain global information on a zip file.
  • Obtain a detailed list of a zip file’s contents via a collection object.
  • Obtain a detailed list of a zip file’s contents via events.
  • Delete files from within a zip file.
  • Delete files after they have been successfully and verifiably zipped.

  • Test the integrity of a zip file and its contents.
  • Process or exclude files based on file attributes, sizes, version resources and dates, or create your own custom include/exclude filters.
  • Wildcard previewing: find out exactly which files will match your wildcards and filters before you start zipping or unzipping.
  • Compression previewing: obtain the compressed file sizes before starting the actual zipping operation. Statistics on the entire group of files to be zipped are also provided.
  • Add and retrieve comments for individual files in the zip file.
  • Get and set the global zip file comment.
  • Automatic full yield so other applications do not halt during processing.
  • Clear disks before writing the zip file to them.
  • Specify the amount of free space to leave on the first disk of a spanned zip file set.
  • Reject disks without specified amount of free space on them when spanning.
  • Compress entire directories and their contents.
  • Process only files newer than those already in the zip file or existing on disk.
  • Provide global encryption and decryption passwords or on a file-by-file basis.
  • Control which types of files are stored in the zip file without compression.
  • Control what path information is stored in the zip file for each file.
  • Store a drive’s volume label in the zip file and restore it during unzipping.
  • Zip up system and hidden files, overwrite read-only files.
  • Allow zipping files that are currently open for write operations by other processes.
  • Limit operation to files with timestamps and file sizes within specified ranges.
  • Supports long filenames and UNC paths, and stores Unicode filenames in the zip file.
  • Manipulate self-extracting zip files without disturbing their self-extracting ability.
  • Rename files and their paths as they are being zipped or unzipped.
  • Rename files in a zip file without unzip and re-zip operations.
  • Change file parameters (comment, time stamps, file attributes) in a zip file.
  • Control the amount of compression applied to files being zipped.
  • Specify the path where files will be uncompressed to.
  • Specify files to process using wildcards.
  • Work on temporary copies of zip files, for maximum safety.
  • Specify the location of where temp files are created.
  • Filter out files during a zip file update, merge, or conversion based on any file attributes or parameters.
  • Set the date of the archive file to the most recent date among the files it contains.

Documentation and samples

  • Complete, comprehensive documentation provided in an MSDN-style HTML format which is fully context-sensitive so that pressing F1 on a keyword in your IDE opens up the manual to the correct relevant topic.
  • Fully commented sample applications for various languages, including VB, Delphi, Visual C++ with ATL and MFC, C++ Builder, and ASP Active Server Pages.

Direct DLL API access

  • The library’s single DLL can also be accessed as a standard 32-bit DLL through its exported API.
  • All properties, methods, and events are exported.
  • All exported API calls involving string parameters come in single, wide character, and Unicode versions.
  • Events can be handled either by callback functions or by windows messages.

Self-extracting Zip file features

  • Create new self-extracting zip files or transform already existing zip files into self-extracting zip files.
  • Self-extracting zip files can span multiple disks.
  • Create self-extracting Zip files for the traditional PKZIP 2.04g compression method. Also now supports the Deflate64™, BZip2, and BWT methods.
  • Create self-extracting zip files that support AES encryption.
  • Creates 32-bit self-extracting zip files that work on all Windows operating systems.

  • Update and reconfigure an existing self-extracting zip file.
  • Customizable introduction message and dialog box titles.
  • Display a license agreement with configurable accept and refuse buttons.
  • Customize all other messages, prompts, and button captions.
  • Customize the self-extracting zip file’s application icon.
  • Set the default unzipping folder.
  • Allow user to select an alternate unzipping folder.
  • Request a password whenever an encrypted file is encountered.
  • The user can enter the decryption password or skip the file if they don’t have the password for the file.
  • Display a text file after successfully unzipping files.
  • Customizable overwrite behavior with dialog box offering the user various overwrite options.
  • Display unzipping status.
  • User interaction and dialogs can be selectively shut off for quiet operation
  • Execute one or more applications (optionally with parameters) or open documents after successfully unzipping files.
  • Copy one or more files from one location to another after unzipping.
  • Register DLLs (or other libraries) on the system after unzipping.
  • Add or change key values in the registry after unzipping.
  • Create self-extracting zip files with a built-in decryption password. This prevents users from using unzipping programs to unzip the files, and therefore forces users to view your custom introduction, license agreement, or warning messages
  • Create program groups and insert items into program groups.
  • Associate filename extensions with applications.
  • Allows 3rd-party install or setup programs (and their data files) to be unzipped into a temporary folder, executed, and then deleted upon completion.
  • Custom paths, filenames, strings, and prompts are parsed, allowing you to insert strings such as the current folder, windows and windows system directories, the temporary folder, and more.
  • Use extra headers such as Unicode filenames, extended filestamps, and security descriptors.
  • Supports the Zip64 zip file format allowing the creation of Zip files of practically unlimited size (no more 4 GB limit), which can contain a practically unlimited number of archived files.