A free, all-in-one Mac maintenance utility — verify system files, clear caches, uninstall apps, and tweak hidden settings — from French developer Titanium Software, since 2003.
Our take
One utility for a long list of maintenance tasks that would otherwise mean typing Terminal commands: verify the startup disk and system file structure, clear caches, uninstall applications, rebuild indexes and databases, and configure hidden preferences in the Finder, Dock, Safari, and other Apple apps. Titanium Software has built and given it away free since 2003, donation-supported. Each macOS version gets its own matching OnyX build — using the wrong one for your OS isn’t supported, per the developer’s own instructions.
- Price
- Free
- License
- Proprietary
- Requires
- A version-specific build per macOS release — the current OnyX 5.0.2 needs macOS Tahoe 26, Apple Silicon or Intel. Older builds are maintained back to Mac OS X 10.2.
- Get it via
- Homebrew · Direct
- Developer
- Titanium Software
Do you use OnyX?
Who made this
OnyX’s own site describes its history in the first person — "Since 2003, I have devoted considerable time to developing these applications" — but is copyright-signed only "Titanium Software," never a personal name.
What it does
System verification and repair
Checks the startup disk and system file structure for issues.
Cleaning and maintenance
Clears caches, rebuilds indexes and databases, removes problematic leftover files.
Hidden settings
Exposes and configures preferences in the Finder, Dock, Safari, and other Apple apps that aren’t in System Settings.
The deal
- Free — donation-supported, per the developer
Worth knowing: Not open source, and not distributed via any App Store — direct .dmg downloads only, matched to your exact macOS version.
OnyX — questions people ask
Is OnyX free?
Yes, free and donation-supported, per the developer.
Do I need a specific OnyX version for my Mac?
Yes — Titanium Software ships a separate OnyX build matched to each macOS version; using one built for a different OS isn’t supported.
Who makes OnyX?
Titanium Software, a French developer that has maintained OnyX since 2003.
Is OnyX free?
Yes — OnyX is free.
Does OnyX work alongside a notch app like Alcove?
Yes — OnyX lives in the screen, so it runs happily alongside any Dynamic Island hub or notch app.
Where can I download OnyX?
OnyX is available via Homebrew, Direct.
Reviews
No public ratings yet. Reader reviews are coming to Kitsmith soon.
Listing hand-verified August 30, 2026 from the developer's site and public sources.
How OnyX compares
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