ARJ Converter
Convert files to and from ARJ online for free. Fast, secure, and high-quality file conversion with no sign-up or software required.
Maximum file size is 1GB
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What is an ARJ file?
The ARJ (Archived by Robert Jung) format is a lossless compressed archive container developed by Robert K. Jung in 1991 for MS-DOS environments, utilizing the LZ77-based Lempel-Ziv-Storer-Szymanski (LZSS) algorithm and Huffman coding. Prominent during the Bulletin Board System (BBS) era for its superior compression ratios compared to PKZIP 1.0, the format supports multi-volume spanning, 32-bit Cyclic Redundancy Checks (CRC-32) for data integrity, and password protection. The file structure consists of a main header followed by compressed file data blocks, making it capable of storing directory trees and file attributes compatible with 16-bit and 32-bit architecture.
How to open an ARJ file
Modern operating systems such as Windows 11, macOS, and Linux do not provide native kernel-level support for decoding legacy ARJ binaries. To extract these archives, users must utilize third-party file compression utilities that include the necessary decompression libraries. 7-Zip is the standard recommendation for Windows environments due to its broad codec support, while macOS users should utilize The Unarchiver; Linux users can access content via the command-line arj or unar packages found in standard repositories.
ARJ Technical Info
- Full Name
- Archived by Robert Jung
- Developed By
- Robert K. Jung
- Initial Release
- 1991
- MIME Type
- application/x-arj
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