Cabinet File

What Does Cabinet File Mean?

A cabinet file (CAB) is a compression file format used by Microsoft installation engines. Many installers use CAB for file compression using a broad range of file headers. Its file extension is .cab.


The CAB file format enables single file compression of multiple files, which facilitates installer package creation. CAB and ZIP archives are similar because each format compresses multiple files into a single file container. A cabinet icon represents ZIP files.

Techopedia Explains Cabinet File

CAB holds multiple files and includes reserved file header space for digital signatures or other data. CAB often attaches to self-extracting programs or installers. Microsoft CAB File (MSCF) markers provide simple identification. MSCF and InstallShield are incompatible file types.

CAB enables the following three different compression formats:

  • Deflate: Lossless data compression algorithm invented by Phil Katz
  • Quantum: Data compression method licensed from David Stafford
  • LZX: Compression algorithm invented by Jonathan Forbes and Tomi Poutanen (This later migrated to Microsoft when Forbes joined the company.)

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Margaret is an award-winning technical writer and teacher known for her ability to explain complex technical subjects to a non-technical business audience. Over the past twenty years, her IT definitions have been published by Que in an encyclopedia of technology terms and cited in articles by the New York Times, Time Magazine, USA Today, ZDNet, PC Magazine, and Discovery Magazine. She joined Techopedia in 2011. Margaret's idea of a fun day is helping IT and business professionals learn to speak each other’s highly specialized languages.