OnyX 4.1

Free Multifunctional utility for Mac OS X.
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Latest version:
4.1.8 See all
Free   4.5 MB
Used by 13,076 people
Awards: Mac Informer Editor Rating 5
Info updated on:

OnyX is an all-in-one system maintenance tool and optimizer. It is a very simple and light application that comes with a variety of maintenance tools that can be run to make sure that you are enjoying your system at its fullest. The first scans that OnyX will make automatically when you run the application for the first time are a S.M.A.R.T status check of your hard drives and the analysis of your startup discs. If the application detects any problems, it will prompt you to carry out a reparation task.

Not everything that OnyX can do deals with hard drives, though. In the main window, there are five categories. The first one is hard drive analysis and restoration, but the following ones allow you to repair the permissions of your system (a common problem with Macs), clear your browser settings, cache, passwords, etc., delete application, user and system caches, and more.

An array of more advanced features is also available. Those allow you to hide or show volumes, repair discs, run custom scripts, among others.

OnyX comes with extensive help and it even includes a glossary with the information about many tasks. Although Macs are known for their stability and lack of errors, it can never hurt to have an application like this.

JF Senior editor
Editor rating:

Screenshots (3)

Review summary


  • Quick analysis
  • Multiple repair options
  • Built-in glossary
  • Several different types of checks


  • Slow when working with certain drives

Comments (4)

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It would be fine, if the updater (mac.informer) verifies the current OS-version before propose the update. Otherwise you have to expect many problems to remove the unmatched version and reinstall the old but working one.

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Don't simply rely on download sites (MacUpdate, etc.). If you go to the developers site, they have versions of Onyx available for old versions of OS X as well as M/L. They say they're soon to release the Mavericks version as well.

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For Mountain Lion only! Does not work with Lion.

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