The Zipx Format

What is a Zipx File?

A Zipx file (.zipx) is a Zip file in which WinZip has used one or more of its available advanced compression methods. The .zipx extension makes it clear that the file was created using an advanced compression method. This helps if you plan to share highly compressed files with others.

Best method compression is the default for creating Zipx files. When using best method, WinZip will create its smallest Zip files. Best method allows WinZip to choose a compression method for each file type, which will usually provide the best result.

!Zipx file received in an email message

The .zipx extension quickly and easily conveys that WinZip, or another compatible compression utility, will be required to open the file. The advanced compression methods used in Zipx files are extensions to the original, open source Zip file format. The particular ones available in WinZip are:

  • BZip
  • LZMA
  • PPMd
  • XZ*
  • MP3^**
  • Jpeg**

  • Wavpack**

  • XZ uses LZMA2 compression and is only available with WinZip 18 or later. ^MP3 compression is only available with WinZip 21 or later. ** MP3 , Jpeg , and WavPack are not available to be manually selected. When Best method compression is being used, WinZip will apply these compression methods whenever you are zipping the file types appropriate for their use.

Of course, you can still choose to create .zip files, which are compatible with most utilities. If you are zipping files using the context menu or using a WinZip Express add-on, you can set the compression method on a case by case basis. Otherwise, you can change the default compression method before creating your Zip file.

If you have any questions about this information, please submit a Technical Support ticket.

What is Zipx?

WinZip® 12.1 introduced the new .zipx file extension, the next step in the evolution of the Zip file format. By using the most recent compression methods to create Zipx files, WinZip 12.1 or later creates WinZip's smallest Zip files to date. The new .zipx file extension also makes it easier to share highly compressed files with others by making it clear that the file was created using advanced methods and that WinZip 12.1 (or later) or another compatible compression utility is required to open the file.

All details associated with creating and reading Zipx files are documented for use by software developers of compression software, anti-virus software, search engines, and other software applications. Please see the WinZip website for the latest details.

Compiled from the official WinZip Knowledge Base (https://kb.winzip.com/)