Operating System Utilities for Mac
OnyX is the main application. The Maintenance, Deeper, and CalHash applications are parts of OnyX.
Thus, if you use OnyX, the Maintenance, Deeper, and CalHash applications are redundant!
Titanium Software has signed all the applications, and Apple has notarized them.
Read the software license agreement carefully before using the applications.

OnyX is a multifunction utility for macOS that you can use to verify the startup disk and the structure of its system files, perform cleaning and computer maintenance tasks, configure some hidden parameters of many Apple applications, and more.
Learn about OnyX...
Maintenance is an operating system maintenance and cleaning utility for macOS that you can use to perform miscellaneous computer maintenance tasks: run periodic scripts; rebuild the databases; delete application, font, and system caches; and more.
Learn about Maintenance...
Deeper is a personalization utility for macOS that you can use to turn on or turn off the hidden functions of the Finder, Dock, Safari, Music, login window, and many Apple applications, and more.
Learn about Deeper...
CalHash is a utility that you can use to calculate and compare a file's checksum (also known as a message digest).
Learn about CalHash...
Access Menu is a customizable utility for macOS that you can use to quickly access the startup disk's folders from the menu bar.
Learn about Access Menu...