30 March 2022
OnyX is a staple program for any serious Mac user for a reason. It has a vast number of valuable utilities that allows you to configure your Mac as you want it without having to search for and use numerous utilities. It would be a no-brainer for that alone but add on the fact that it's free and developed specifically for each new version, and this software becomes a must-have.
For any serious Mac user, particularly one who's used Macs for a long time, OnyX is a vital part of their Mac toolbox. Released during the Jaguar 10.2 version of the OS X, it has an impressive range of functionality. The app brings together some of the Mac's inbuilt functions allowing users to correct problems and gremlins in their macOS.
OnyX was developed in 2003 by Joël Barrièrehas, and he has worked steadily on it ever since, updating it for each new version of OS X. Massively customisable, it allows you to verify your start-up disk, reorganise your file structure, rebuild databases, adjust and repair file permissions and recreate indexes. The final icing on the cake of this great utility is that it's completely free to use.
You can download it for free right here but be sure to choose the correct version for your macOS. One slight downside is that OnyX needs to be revised for each new version, so if you like to be an early adopter of each new macOS you may need to wait a little while for a new copy of OnyX.
When you open OnyX for the first time, it tells you you need to allow full disk access for it to work. There are full instructions given on how to do it. You will also need your administrator password to grant access.
OnyX can be customised as much as you wish to suit your needs which is a huge benefit. A minor downside of this is that you need to take a little time to become familiar with how the software works. Luckily the dashboard is simple, clean and easy to figure out. It is split into different tabs depending on the type of maintenance you want to carry out
The maintenance tab is your first port of call if your Mac is starting to run a little slowly. From here, you can verify the file structure and rebuild the spotlight index as well as your mailboxes. Most of the time, however, you'll probably go straight to the cleaning section at the bottom.
There are four options here, system, applications, internet and logs. You'll also find an options button that allows you to fine-tune what you want to remove. Cache files, cookies and log files are fairly safe options to remove, and as they can become fairly large will have a positive impact on how the Mac runs.
In the misc section, there are options to clear old font caches and junk. Be careful with recent items, though, as if you regularly use it to access files you open a lot, you should make sure it's unticked.
When you click execute, the process begins, and you may need to restart a couple of times. Unlike some of the paid-for programs available, you won't get many progress bars or a report back on how much data or how many files have been removed. Emphasis has been placed on functionality rather than displays.
I ran a clean with all the options in clean and misc ticked, as well as choosing to verify the file structure. The test machine is a 2018 Mac Mini six-core Intel i7 3.2GHz. It took 15 minutes to complete, which isn't bad as no maintenance had been run on this particular machine for almost a year.
Depending on the spec of the system, the number of junk files, and if you choose to manually select what to delete, you might find this time increases.
There are a lot of options in here. Some can be useful regularly, and others will only be necessary occasionally. For example, OnyX pulls together all the built-in UNIX manuals, and it's unlikely you'll spend much time looking through these. You also have the option to create a Time Machine snapshot or delete them all. Snapshots normally run on a schedule, so they aren't needed ad-hoc, and you'd only want to delete them all if you'd transferred them to a hard drive or cloud drive and were looking to save space.
The ones you will find useful are options to show hidden files and folders — there are a surprising amount of these in macOS, and File System will check and verify the structure of the files in the same way the one in Maintenance did.
The Files tab allows you to delete files and folders in a secure manner, so if you're dealing with sensitive data, this is ideal. Simply emptying the trash is not enough to fully remove the files, and utilities out there can restore this data. The other options in this tab you would only need once in a blue moon.
One final key function is found on the info tab. This is where you’ll find the protection tool. This lists all the malware recognised by the os protection system XProtect. You can also scan any items you have downloaded to locate and delete malware.
The parameters tab allows you to set the file format of screenshots as well as where the file saves to by default. It also allows you to set the number of recent items you can see and add a message to your Lock Screen. It's a great configuration tool.
As explained above, OnyX is completely free. You can download it, use it as much as you like, and even share it with others, all without it costing you a penny.
If you would like to reward the developer for this software, though, there is an option to make a donation. How much you choose to donate is left entirely up to you.
OnyX is without a doubt one of the most versatile apps to keep in your Mac repair kit. You can verify file structures, remove files securely and perform a clean to remove old files and other junk to ensure faster running. Many of these items are already available in macOS but OnyX brings them together in a single interface making maintaining and configuring your Mac much easier. OnyX would be an essential app if you had to pay a subscription fee but as a free to own product it becomes an absolute no-brainer.
OnyX has few rival products because of the range of its functionality. However, if you're looking for a more user-friendly product to clean your Mac, then MacKeeper and CCleaner for Mac are both good choices. You will have to pay for these though, MacKeeper starts at $10.95 per month per one Mac and CCleaner for Mac is $19.95.
If you want a product to optimise your Mac, then Cocktail is available. It offers some of the same functions as OnyX and costs $19.99 per year.
Content Manager for the MacUpdate blog
Ruslana is a passionate Mac admirer and tech writer with 5+ years of experience in Mac support.