Convert A01 to 7-Z

Understanding a01 and 7-z file formats

A01 files are part of a multi-volume archive set created by the ARJ compression utility, commonly used in the 1990s and early 2000s. These files are not standalone archives but segments (e.g., .a00, .a01, .a02, etc.) of a larger compressed archive. To extract the contents, you need all parts of the archive set.

7-Z files refer to the 7z format, a modern, high-compression archive format developed by the 7-Zip project. 7z files support strong AES-256 encryption, high compression ratios, and are widely supported across platforms.

How to convert a01 to 7-z format

Since .a01 files are only a part of a split archive, you must first reassemble and extract the complete archive using all its parts. Once extracted, you can recompress the contents into a .7z archive.

Step-by-step conversion process

1. Gather all parts of the ARJ archive (e.g., .arj, .a00, .a01, etc.) in the same folder.
2. Extract the archive using a tool that supports ARJ, such as 7-Zip or WinRAR:
   • Open 7-Zip File Manager.
   • Navigate to the folder with your ARJ parts.
   • Right-click the .arj or first part, select 7-Zip → Extract Here.
3. Compress the extracted files into a 7z archive:
   • Select the extracted files/folder.
   • Right-click and choose 7-Zip → Add to archive....
   • Set Archive format to 7z and click OK.

Best software for a01 to 7-z conversion

The recommended tool for this process is 7-Zip (free, open-source, Windows/Linux). It supports both ARJ extraction and 7z compression. WinRAR is another option, but 7-Zip is preferred for its 7z support and cost-free license.

Summary

To convert a01 (ARJ split archive part) to 7z, extract the full ARJ archive using all parts, then recompress the contents into a 7z file using 7-Zip.