ZPAQ

File Format
Name	ZPAQ
Ontology	Electronic File Formats Archiving ZPAQ
Extension(s)	.zpaq, .cfg
PRONOM	fmt/1097
Released	2009

ZPAQ (or zpaq) is a compressed archive format, and associated software. It is a member of the PAQ family of formats.

Apparently, a capitalized ZPAQ usually refers to the format, while zpaq refers to the software.

ZPAQL

To the best of our understanding, ZPAQ decompression algorithms are written in a special programming language called ZPAQL (which apparently uses the .cfg file extension), compiled to bytecode, and stored in each ZPAQ archive. This allows ZPAQ to use practically any compression algorithm.

Identification

Most or all ZPAQ archives begin with ASCII "zPQ", or "7kSt".

Specifications

• The ZPAQ Open Standard Format, Version 2.06
• The ZPAQ Compression Algorithm

Sample files

• ZPAQ website → test case (calgarytest2.zpaq)
• ZPAQ Utilities → pi10k.zpaq

Links

• ZPAQ website
• Wikipedia article