WinZip is a straightforward, fast, and easy-to-use zipping and unzipping utility that includes built-in support for popular Internet file formats such as TAR, ZIP, UUencode, XXencode, BinHex, MIME, and Unix-compressed files. Older ARC, ARJ, and LZH files are supported via external programs. In version 8.1, enhanced Explorer integration adds more options to the Explorer context menu and allows you to unzip several archives at once; compress several small ZIP files for easy sending via an e-mail attachment or as an alternative to disk spanning; a new Quick Pick taskbar icon gives you instant access to WinZip and recently used ZIP files; WinZip Wizard enhancements allow you to run installation files included in ZIP archives and extract files from split ZIP files and multiple disk ("spanned") ZIP files; and support for Windows XP allows WinZip to run as a native Windows XP program with no need to set the compatibility mode.

WinZip 9.0 supports 128- and 256-bit key AES encryption, which provide much greater cryptographic security than the traditional Zip 2.0 encryption method used in earlier versions of WinZip. WinZip 9.0's advanced encryption (FIPS-197 certified) uses the Rijndael cryptographic algorithm which, in 2001, was specified by the National Institute of Standards and Technology (NIST) in Federal Information Processing Standards (FIPS) Publication 197 as the Advanced Encryption Standard (AES). After a three-year competition, the AES was announced by NIST as an approved encryption technique for use by the U.S. government, private businesses, and individuals. When properly implemented as a key component of an overall security protocol, the AES permits a very high degree of cryptographic security, yet is fast and efficient in operation. WinZip's AES encryption is just as easy to use as traditional Zip 2.0 encryption: all you have to do is select the encryption strength and specify your password.