|This article concerns the 64-bit extension to the Zip file format. This extension does not involve or require a 64-bit version of Windows.
In addition to supporting the original Zip file format, WinZip also supports the 64-bit extensions to the Zip file format. The extended format lets you store all the data you need in Zip files of virtually unlimited size.
The original Zip file format limited the number of member files in a Zip file to 65,535, and the maximum size of both the Zip file itself and any member file to 4 gigabytes. 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.
WinZip remains fully compatible with the original Zip file format and uses the original format whenever possible. WinZip uses the 64-bit extended format only when the file you create exceeds the original limits.
Note: If you receive or share Zip files that use this 64-bit Zip file extension, a Zip file utility, such as WinZip, that supports this format will be necessary to open and use these Zip files.
For more information, please see the article Information about size limits with WinZip.