ARJ

This article is about the compressed file format. For other uses, see ARJ (disambiguation).

Archived by Robert Jung

Filename extension	.arj
Uniform Type Identifier (UTI)	public.archive.arj
Developed by	Robert K. Jung
Type of format	archive format

ARJ (Archived by Robert Jung) is a software tool designed by Robert K. Jung for creating high-efficiency compressed file archives. ARJ is currently on version 2.86 for DOS and 3.20 for Windows and supports 16-bit, 32-bit and 64-bit Intel architectures.

ARJ was one of two mainstream archivers for DOS and Windows during the early and mid-90s, with PKZIP being its competition. Parts of ARJ were covered by U.S. Patent 5,140,321. Generally ARJ was less popular than PKZIP, but it did enjoy a niche market during the BBS era and in the warez scene. This was largely due to ARJ's creation and handling of multi-volume archives (archives which are split into smaller files which are then suitable for dial-up transfers and floppy distribution) being more robust than PKZIP's.

File format support in other software

ARJ compressed files with the Filename extension .arj can be unpacked with various tools other than the ARJ software. There exists a free software re-implement of the tool. The software 7-Zip and Zipeg can also unpack .arj files. For Mac there exists a standalone utility UnArjMac.

See also

• JAR, an archiver by the same author
• List of archive formats
• List of file archivers
• Comparison of file archivers

External links

• ARJ Software Inc. (proprietary version)
• Open Source version of the ARJ archiver