Description |
RAR5, or the Roshal ARchive format version 5, the current version (as of April 2017), was released in April 2013 and is supported by WinRAR 5.0 and later. See RAR_Family for details on the file structure.
There are significant changes in the format structure, compression algorithm and encryption algorithm.
Format changes:
- Time stamps are stored as Coordinated Universal Time (UTC) instead of former local time
- File names and archive comments are stored in UTF-8 encoding format
- Change to 256 bit length BLAKE2sp hash instead of 32 bit CRC32 checksum
- Maximum path length is increased up to 2048 characters.
- Maximum comment length for RAR archives is increased from 64 to 256 KB
- Includes the optional "quick open information" to allow the archive contents to open faster in WinRAR.
Compression algorithm changes:
- Maximum compression dictionary size is increased up to 1 GB in 64 bit WinRAR. 32 bit WinRAR version can use up to 256 MB dictionary when creating an archive. Both 32 bit and 64 bit versions can unpack archives with any dictionary size, including 1 GB
- Increased default dictionary size to 32 MB resulting in a higher compression ratio and faster speed over RAR4 (which had 4 MB).
- Includes Intel IA-32 executable and delta compression algorithms
- Removes supports for specialized text, multimedia, and Itanium executables compression algorithms
Encryption algorithm changes:
- Encryption algorithm is changed from AES-128 (in RAR4) to AES-256
- Increased default dictionary size to 32 MB resulting in a higher compression ratio and faster speed over RAR4 (which had 4 MB).
- Changes in special password verification values allow many wrong passwords to be detected without having unpack the entire file
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