Comparison of archive formats

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There are many popular archive formats used to create archive files. The tables below compare many popular archive formats.

Table Columns

The table columns contain the following general information:

Purpose

The earliest use of archive formats was for backup, mobility, and archiving. Improved versions of archive formats added the ability to compress the data to consume less storage space and network bandwidth. There are multiple compression algorithms available to statistically compress data. Some kinds of data can be highly compressed and some kinds of data do not benefit from compression. Currently, archive formats are also used to package software files for distribution, installation, and execution.

Filename Extension

The DOS and Windows operating systems required filenames to include a three-character extension to identify the file type and use. Filename extensions were (and are) required to be unique for each type of file. Many operating systems can identify a file's type from its contents without the need for an extension in its name. However, the use of three-character extensions has been embraced as a useful shorthand for identifying file types.

Integrity Check

Archive files are often stored on magnetic media, which is subject to data storage errors. Early tape media had a higher rate of errors than is expected for magnetic media today. Many archive formats contain extra data embedded in the files in order to detect data storage or transmission errors, and the software used to read the archive files contain logic to detect errors.

Recovery Record

Many archive formats contain redundant data embedded in the files in order to detect data storage or transmission errors, and the software used to read the archive files contain logic to detect and correct errors.

Encryption

In order to protect the data being stored or transferred from being read if intercepted, many archive formats include the capability to encrypt the data. There are multiple mathematical algorithms available to encrypt data.

Table of Comparison

The following table compares archive formats used for computer backups or transferring files.

Notes

Note 1: While the original tar format uses the ASCII character encoding, current implementations use the UTF-8 (Unicode) encoding, which is backwards compatible with ASCII.
Note 2: Supports the external Parchive program (par2).
Note 3: From 3.20 release RAR can store modification, creation and last access time with the precision up to 0.0000001 second. [1]

See also

• List of archive formats
• Comparison of file archivers
• Comparison of file systems
• List of file systems