OnyX is a utility tool that performs tasks such as verifying system files, executing maintenance and cleaning tasks, and configuring parameters in various Apple applications. It can also delete caches, remove problematic folders and files, and rebuild databases and indexes.

OnyX is designed for each major operating system version, and using the correct version for your operating system is essential to avoid errors.

Recent updates to OnyX include improved deletion of APFS snapshots, application caches, and logs. An Uninstall pane has been added, and the option to change icon spacing in the menu bar is now available. The visibility of volumes has been enhanced, and the User Guide has been updated and improved. Corrections have been made to the Info pane and screen capture path. New features include the sm3 algorithm for checksum calculations, the ability to change the login window background image, and options to adjust column sizing in Finder windows and slow-motion effects. The Spotlight index rebuilding process has also been optimized.