German developer win.rar GmbH has released WinRAR 7.0, a major new update to its powerful archiving tool for Windows.

Capable of opening a wide range of archive file types, from ZIP to CAB, GZip and ISO, WinRAR 7.0 focuses on introducing several improvements to its primary RAR format.

The big improvement in WinRAR 7.0 comes with newly added support for compression dictionary sizes larger than 1GB in size. Increasing this size can boost compression ratios on archives containing large files with repeated blocks of data, such as virtual machine disk images.

Version 7.0 supports compression dictionary sizes all the way up to 64GB; furthermore, users aren’t restricted to power of 2 sizes, allowing custom sizes such as 5GB or 22GB to be configured for use under Settings > Compression.

Several safeguards have been built in – the WinRAR command line tool refuses by default to extract archives with dictionaries over 4GB in size, for example. This is done to prevent unexpected excessive memory allocation that could cause performance issues on the PC extracting the file.

Other improvements include the addition of an alternate search algorithm, optimised for locating longer and more distant data blocks. In addition to improving the compression ratio, it can also occasionally speed up the compression time for files containing large amounts of redundant data.

The feature does come with increased memory overheads, and can have the opposite effect on compression times with certain data types. It’s not enabled by default – do so via the 'Long range search' options under 'Advanced compression parameters'.

The new release also drops support for creating older RAR (4.x) archives, although the app can still decompress existing RAR 4.x files. For a complete summary of the lengthy list of new features and improvements, check the program’s release notes.

A free trial version of WinRAR 7.0 is available now for PCs running Windows 7 or later. The full version can be purchased for €29.95 ($36.50) plus tax.