Overview
WinRAR and the RAR file format has evolved over time. Starting with WinRAR version 5, support for a new archive format RAR5 was added, incompatible with the previous one, but also using the same RAR file extension.[5] With the introduction of RAR5, the older RAR file format is now referred to as RAR4. WinRAR version 5 can read or write RAR4 or RAR5 archives, but older WinRAR doesn't support RAR5 archives.[6]
The new RAR5 file format added numerous features, but removed comments for each file (though archive comment still remains), authenticity verification, and compression algorithms for specialized text and multimedia. RAR5 also changed the file name for split volumes from "archivename.rNN" to "archivename.partNN.rar".[6]
The RAR5 file format increased the maximum dictionary size to 1 GiB, thus allowing a WinRAR user to choose between 11 different compression directory sizes from 1 MiB to 1 GiB, with the default in version 5 increased from 4 MiB to 32 MiB, typically achieving a higher compression ratio.[6]
RAR5 also enhanced or added optional features: optional AES encryption was increased from 128- to 256-bit, option for 256-bit BLAKE2 file-hashing algorithm instead of default 32-bit CRC32, optional duplicate file detection, optional NTFS hard and symbolic links, optional Quick Open record to allow large archives to be opened faster, maximum path length for files in RAR and ZIP archives is increased to 2048 characters.[6]
Features:
Packing (creation) of RAR or ZIP archives.
Unpacking of ACE, ARJ, BZIP2, CAB, EXE, GZ, ISO, JAR, LHA, RAR, TAR, UUE, XZ, Z, ZIP, ZIPX, 7z archives.[6][7]
Checksum (integrity) verification for ACE, ARJ, BZIP2, CAB, GZ, BZIP2, RAR, XZ, ZIP and 7z archives.
Multithreaded CPU compression and decompression.
When creating RAR archives:
Support for maximum file size of 16 EiB (264 bytes) minus 1.
Compression dictionary from 1 MiB to 1 GiB (limited to 256 MiB on 32-bit And 64-bit Windows, however 32-bit And 64-bit Windows still can decompress archives with 1GiB dictionary). Default size is 32 MiB.[6]
Optional 256-bit BLAKE2 file hash can replace default 32-bit CRC32 file checksum.[6]
Optional encryption using AES (Advanced Encryption Standard) with a 256-bit key.[8]
Optional data redundancy is provided in the form of Reed-Solomon recovery records and recovery volumes, allowing reconstruction of damaged archives.
Optional "Quick Open Record" to open RAR files faster.[6]
Ability to create multi-volume (split) archives [9][10]
Ability to create self-extracting files. The self-extractor can execute commands, such as running a specified program automatically after self-extraction.[11]
Support for advanced NTFS file system options, such as NTFS hard and symbolic links.[6]
Support for maximum path length up to 2048 characters (stored in the UTF-8 format).[6]
Optional archive comment (stored in the UTF-8 format).[6]
Optional file time stamp preservation: creation, last access, high precision modification times.
Optional files deduplication.