At one time, the maximum file size allowed by the Zip file specification was 4 gigabytes. This limit applied both to the uncompressed and compressed sizes of files inside Zip files (.zip or .zipx), and also to the total size of a Zip file itself. In particular, this 4-gigabyte limit applied to WinZip versions 7.0 to 8.1 SR-1.
If you had attempted to add or update a file that is greater than 4 gigabytes, WinZip versions prior to WinZip 9.0 issue the following message:
The file is too big to be stored in a Zip file and will be skipped.
WinZip versions 7.0 to 8.1 SR-1 support archives that contain up to 65,535 files and foldernames. This is a Zip format limitation.
That being said, starting with WinZip 9.0 and WinZip Command Line Support Add-On 1.1 (released in 2004), and up to the current release of WinZip and the WinZip Command Line Support Add-On, all support the 64-bit extension to the Zip file format.
For all practical purposes, the 64-bit extended format eliminates all these restrictions. Using the extended format, the member file size, Zip file size, and number of member files you can add to a Zip file are limited only by your system's resources.
With the 64-bit extensions to the Zip file format enhancement, archives of 18,446,744,073,709,551,615 bytes (2 to the 64th power) are possible. This is 16 exabytes, or over 16 billion gigabytes. Over 4 billion files and folders can be included in an archive.
In order to take full advantage of the extended format, one must be using a version of Windows that supports such large files (for example, a large NTFS partition running on the NT family of operating systems, which includes Windows 2000, Windows XP, and Windows Vista).
Note: members of the Windows 9X family of operating systems (Windows 95, Windows 98, Windows Me) use only the FAT file system which does not have support for very large files. For a detailed description of the NTFS and FAT file systems and their size limitations, please read the Microsoft TechNet article Working with File Systems.
Also, the maximum length of a fully qualified file name (path + name) is 250 characters. This is a limit built into Windows, not of WinZip nor of the Zip file format. There is no direct limit on number of directory levels allowed in a path name; the character length limit prevents too many levels from being added.
