|
WinRAR and the RAR file format have evolved over time. Support for the archive format RAR5, using the same RAR file extension as earlier versions, was added in v5;[7] files in the older RAR file format are now referred to as RAR4. WinRAR versions before 5.0 do not support RAR5 archives.[8]
The RAR5 file format added some features, but removed comments for each file (though archive comment still remains), authenticity verification, and specialized compression algorithms for text and multimedia files. RAR5 also changed the file name for split volumes from "archivename.rNN" to "archivename.partNN.rar".[8]
The RAR5 file format increased the maximum dictionary size to 1 GiB; 11 different compression directory sizes from 1 MiB to 1 GiB are available, with the default in version 5 increased from 4 MiB to 32 MiB, typically improving compression ratio. AES encryption, when used, was increased from 128- to 256-bit. Maximum path length for files in RAR and ZIP archives is increased to 2048 characters.[8]
Options added in v5 include 256-bit BLAKE2 file-hashing algorithm instead of default 32-bit CRC32, duplicate file detection, NTFS hard and symbolic links, and Quick Open record to allow large archives to be opened faster.[8]
Features[edit]
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, 001 (split) archives.[8][9]
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 Windows, however 32-bit Windows still can decompress archives with 1 GiB dictionary). Default size is 32 MiB.[8]
Optional 256-bit BLAKE2 file hash can replace default 32-bit CRC32 file checksum.[8]
Optional encryption using AES (Advanced Encryption Standard) with a 256-bit key.[10]
Optional data redundancy is provided in the form of Reed-Solomon recovery records and recovery volumes, allowing reconstruction of damaged archives (including reconstruction of entirely missed volumes).
Optional "Quick Open Record" to open RAR files faster.[8]
Ability to create multi-volume (split) archives[11][12]
Ability to create self-extracting files. The self-extractor can execute commands, such as running a specified program automatically after self-extraction.[13]
Support for advanced NTFS file system options, such as NTFS hard and symbolic links.[8]
Support for maximum path length up to 2048 characters (stored in the UTF-8 format).[8]
Optional archive comment (stored in the UTF-8 format).[8]
Optional file time stamp preservation: creation, last access, high precision modification times.
Optional files deduplication.
License[edit]
The software is distributed as "try before you buy"; it may be used without charge for 40 days.[14]
Although archiving with the RAR format is proprietary, RarLab supplies as copyrighted freeware the source code of the UnRAR unpacker, with a license allowing it to be used in any software, thus enabling others to produce software capable of unpacking, but not creating, RAR archives.[15] |
