• Cross-platform file compression, encoding for Macintosh (also decompression, decoding)
• Cross-platform file compression, encoding for Windows (also decompression, decoding)

The most common file compression standards differ on Windows and Macintosh. For Windows, .ZIP is most common, and on Mac, .SIT (StuffIt) is common. Cross-platform software can compress or decompress .SIT on Windows, and .ZIP on Mac, in addition to other formats. Some of these tools can also compress/decompress Unix formats, such as TAR and GZIP. Many of these third-party utilities can also decode Mac or Windows encoding schemes.

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Cross-Platform File Compression and Encoding for Macintosh:

Company	Product	Description
Allume Systems	StuffIt Deluxe 12.0 for Mac	The most complete archiving solution. Compresses and decompresses in Mac, Windows, and Unix archive formats, and more types of files than any other solution. Also encodes/decodes Windows email encoding formats. Compression formats supported: .sit, .sitx (for higher compression), .zip, .exe, .sea, .tar, .bin, .hqz, .gz (gzip), .bz2, .tgz, .lha, .rar, .arc, .pf , .uu, .uue, .cab, .yenc, and .z (also known as Unix Compress) Encoding/decoding formats (used in email) supported: Base64/MIME, UUencode (.UU), BinHex (.HQX), .LHA, MacBinary (.BIN), AppleSingle, AppleDouble Image, audio compression: Version 12 added the ability to compress cross-platform file formats that are already compressed, including MP3, PDF, Photoshop, TIFF, PNG, GIF, BMP. It increases compression of JPG files to 30 percent. StuffIt uses a different compression algorithm for each type of file to get optimized reduction in size. The compression is lossless, without degrading the image or sound quality. It can also re-compress zip archives: unzip an archive, the recompress using an optimized compressor for each type of file. Other features: Built-in archived backup to FTP, optical disk, or folder Joins segmented StuffIt files. StuffIt commands in Mac OS X contextual menu Creates self-extracting archives Windows .EXE archives on the Mac. Now creates .uu and .zip archives by adding or removing the UUencode (.uu) or Zip (.zip) suffix, those files will encode, compress or expand Create and expand Bzip (.bzip) files (common to the Unix) Can view JPEG thumbnails without decompressing
	StuffIt Expander 12.0 Mac (free)	A drag-and-drop decompressor/decoder. (Does not compress or encode.) Decompresses .SIT, .ZIP, GZIP (.GZ), .TGZ. Decodes UUencode (.uu, .uue, .enc), BinHex (.hqx all versions), MacBinary (.bin all versions). Decypts Private File (.pf ). Mounts disk images (.img, .smi) and ShrinkWrap(tm) or Apple's Disk Copy. Ships with Mac OS.
Thomas Brown (shareware author) email	ZipIt (shareware)	Compresses and decompresses ZIP. Easy to use, supports drag and drop compressing and decompressing of files. Includes an option for MacBinary for retaining resource fork and Type and Creator code for Mac files transferred to Mac users. A solid utility that has been around for many years. Now also opens Windows "self extracting" .EXE archives.
Apimac	Compress Files	Mac OS X utility for compressing, archiving, and encrypting files in Windows and Unix/Linux formats. Compress Files will also omit Mac-specific invisible files (such as the .DS_Store files). Compress Files can also create Zip compressed files and encryped Zip archives.; TAR archives; Gzip compressed archives; Bzip2 compressed archives; compressed and encrypted Zip files and compressed and encrypted disk images. Version 3.0 added the ability to create XAR (eXtensible ARchive format) archives, a new open source archive format that Apple started to use in Mac OS X 10.5 Leopard.
Brian Clark	YA-Decoder (Yet Another Decoder) Mac OS 8 and 9 only (no OS X) (Shareware)	A simple droplet designed to decode MIME Base64 (including AppleSingle and AppleDouble), BinHex, MacBinary (including MacBinary III), and uuencoded files that are dropped upon it. It assumes that all segments of the original encoded document have been concatenated into the file being decoded, and that the segments are in order. Intended as a helper application for decoding Usenet binary attachments. (Not a general purpose decoder.) It can deal with multiple attached files, and can combine and decode MasterSplitter files created on a PC.
DataViz Merritt Corporate Woods, 612 Wheelers Farms Road Milford, CT 06460 203-268-0030 800-733-0030 Fax: 203-268-4345	MacLinkPlus Deluxe	The ultimate file translator for Mac. Can convert Mac and PC word processing, spreadsheet, database, and graphics file formats. Also does the best job at recognizing, decoding and decompressing email attachments. Encoding formats include Binhex, MIME, Uuencode. Decompression formats include StuffIt, Zip, Compact Pro, MacBinary, Gzip, TAR, Z.
Dare to be Creative	iArchiver (shareware)	A shareware compression utility. Its notable feature is the ability to convert whole archives between several Unix formats (such as RAR and TAR), ZIP, and Apple's .DMG disk image format. iArchiver can also compress and decompress in various Unix, Zip, and Mac formats, including SIT, and can encode/decode MacBinary and BinHex. (.EXE archives are not supported.)
Etresoft	Decoder 2.1	A utility for Macintosh and Windows that can decode files encoded in Mac, Windows, and UNIX standards, including AppleSingle, BinHex, MacBinary (versions I, II, and III), UUencoded, and MIME formats. Useful for opening email-attached files from Windows users.
Felt Tip Software	Decode da Code (shareware)	A Macintosh helper application for e-mail and Internet News programs (such as NewsWatcher) for decoding MIME Base64 and uuencoded files. The developer claims it is the "fastest way to decode binary newsgroup postings on the Mac." It can figure out multipart MIME mail messages, including ones in the AppleDouble format, and parse long filenames. Decode da Code uses Internet Config to set the appropriate file type and creator codes, and to post-process the decoded file.
Simon Fraser	MT NewsWatcher (free)	A Usenet newsreader for Mac that can rejoin segmented Usenet binaries.
Gwenole Beauchene	Mac UnAce	A tool by that decompresses ACE archives on Macintosh.
Dirk Haase email	MacZip (also known as Zip for Macintosh) Mac OS 7/8/9 only (no OS X) (freeware)	A utility that can compress and decompress in the PC-standard Zip format. MacZip is a free port of the Info-ZIP utility.
Jean-loup Gailly	MacGzip (freeware)	Compresses and decompress the GNU zip (.gz) format, popular on UNIX and the Internet. The program and the source code are both free.
Guy Levasseur	PifPafZip and PifPafUnzip (freeware) (Web page in French)	Drag-and-drop Macintosh utilities that create and open zip archives. Optimized for files with French names.
MindVision	MindExpander	Free utility for expanding and decompressing in .sit, .sea, .zip, .bin and .hqx formats. It does not, however, support the current SIT 5 format. (Similar to StuffIt Exander, though not as many formats supported.) Also available for Windows.
MacIt Better	BetterZip	BetterZip is a Cocoa application that can archive and decompress in multiple Windows and Linux/Unix formats, including zip, jar, war, ear, tar (tar, tgz, tbz), gzip, and bzip2. Unlike the built-in zip feature of Mac OS X, BetterZip can handle multiple files. The developer, Robert Rezabek, told us of another feature not found ZipIt: BetterZip has a function to "clean" archives: It will remove resource forks and Finder settings from the archive (those ugly  __MACOSX folders and ._ files) when you need to exchange data with Windows or Linux users.
Stone Design	Pack Up and Go (for Mac OS X) (shareware)	Compression and decompression in Gzip (.gz), .Z, and tar via drag and drop.Will also do uuencoding for e-mail attachments. A Jobs Panel keeps track of all compressions in a session.
Strout.net	MacTar	Compresses and decompresses files in "tar" (tape archive) format used on Unix. It works with both tape and floppies.
TechSono Engineering	PixMachineMac	Autility for the Mac that can join segmented files posted at Usenet groups by PC users. Windows users often segment files using a program call MasterSplitter before posting them to Usenet newsgroups. There is no version of MasterSplitter available for the Mac. PixMachineMac is primarily a Usenet download utility that can detect MasterSplitter files, save them to a Mac, and decode them using the handy MasterSplitter Widget. As far as we know, no other MacOS newsreader can do this.
Vampire Software	SmartZip	A new, low-cost shareware zip compression utility. Vampire says it is compatible with WinZip for Windows and maintains Mac file information when moving to PCs. Vampire also says it is fast an has an easy-to-use interface (screen shots at the web site).

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Cross-Platform File Compression for Windows: