At a glance
| CleanMyMac | OnyX | |
|---|---|---|
| Price | $39.95-89.95/year (or $119.95 lifetime) | Free (donationware) |
| Interface | Modern, guided, simplified | Dated, dense, more manual |
| What it does | Junk cleanup, malware scan, memory, uninstaller, and more | Maintenance scripts, cache clearing, hidden setting toggles |
| Support model | Company support, regular releases | Community and developer support, monthly updates |
| Made by | MacPaw | Titanium Software |
| Best for | People who want guided, automatic cleanup | People comfortable running maintenance scripts manually |
Two different philosophies
CleanMyMac is built for people who want a guided experience: run a scan, review a simplified summary, click a button, done. It presents its findings in plain language and handles decisions on your behalf where reasonable. OnyX takes the opposite approach. It exposes the actual maintenance scripts and hidden system settings macOS has always had, in a dense, checkbox-heavy interface that has changed little in twenty years. There's a live MacRumors forum thread specifically debating this exact pairing, which tells you it's a real decision people wrestle with, not a hypothetical one.
Both can run the standard Unix maintenance scripts (daily, weekly, monthly cache and log rotation) that macOS schedules automatically but that occasionally benefit from a manual nudge. CleanMyMac wraps this in its broader "system junk" feature; OnyX exposes it directly under its Maintenance tab, alongside dozens of other toggles most users will never need.
Where CleanMyMac wins
Approachability. If the idea of a Utilities-style dense interface is intimidating, CleanMyMac's guided design is a real advantage. You don't need to know what any of the settings mean.
Breadth beyond maintenance. Malware scanning, memory optimisation, and app uninstalling are all bundled in, which OnyX doesn't attempt to cover.
Company support. MacPaw is a company with dedicated support staff, versus OnyX's community-and-developer model, which matters if you want responsive help.
Where OnyX wins
Price. Free, forever, with an optional donation, against $39.95-89.95 a year with no free tier.
Transparency. OnyX shows you exactly which script or setting each option runs or toggles, rather than abstracting it behind a simplified summary. For users who want to understand what's actually happening, that's valuable.
Track record. OnyX has been maintained continuously since 2003, longer than CleanMyMac has existed, by a developer with a long, uneventful safety record in the Mac community.
The honest caveat about OnyX
OnyX's interface is genuinely intimidating on first open. Most users only ever need the Maintenance tab; the rest of the app (dozens of tabs covering hidden Finder settings, automation options, and system verification tools) is there for power users and can safely be ignored by everyone else. If you try OnyX expecting something like CleanMyMac's simplicity, the mismatch in expectations is the most common source of frustration in forum discussions of this pairing.
Which one should you use?
If you want a guided, hand-held experience and don't mind paying a subscription for it, CleanMyMac is the more approachable choice. If you're comfortable with a dated interface in exchange for free, transparent, community-trusted maintenance tools, OnyX does the same core job at no cost, provided you stick to the Maintenance tab and ignore the rest.
For a wider view of what maintenance actually does or doesn't achieve on modern macOS, see do Macs need maintenance, and for CleanMyMac's full feature-by-feature alternatives, CleanMyMac alternatives.
What OnyX's Maintenance tab actually runs
Concretely, the scripts behind OnyX's Maintenance tab are the same ones macOS itself schedules automatically in the background: daily, weekly, and monthly periodic tasks that rotate log files, rebuild certain system databases, and clear specific temporary caches. On a Mac that's rarely fully shut down or restarted for long stretches, these scheduled runs can be delayed, which is the actual (narrow) case for running them manually now and then. CleanMyMac's "System Junk" feature covers overlapping ground but bundles it with additional cache categories the company has identified through its own research, rather than exposing only the standard Unix scripts OnyX surfaces directly. Neither approach fixes a genuinely broken Mac; both are closer to routine tidying than repair.
A smaller, unrelated option worth knowing
We make Shiny, a $4.99 menu-bar app that frees memory, disclosed here for transparency. Neither CleanMyMac's nor OnyX's maintenance features are really about memory pressure specifically; if that's your actual complaint rather than junk files or hidden settings, a narrower tool like Shiny addresses it more directly, and Shiny vs CleanMyMac covers that comparison in full.
A reasonable way to trial both before paying anything
Since OnyX costs nothing, there's little downside to installing it first, running only the Maintenance tab, and seeing whether it makes any noticeable difference to how your Mac feels. If it doesn't, you've lost nothing but a few minutes, and you can look at CleanMyMac's free scan (which shows findings before requiring payment to act on them) to see whether its guided summary surfaces anything OnyX's scripts didn't touch. Comparing the two starting points, rather than assuming either one automatically, is the more honest way to decide which philosophy actually suits how you use your Mac.