Download of OS Cleaner 12.5.16 for Mac was available from the developer's website when we last checked. We cannot confirm if there is a free download of this app available. This free Mac app was originally produced by nara.luna. We recommend checking the downloaded files with any free antivirus. The program lies within System Tools, more precisely System Optimization.
From the developer:
For the Health of your Mac! (Perfect support for macOS High Sierra)
OS Cleaner scans every inch of your system, removes gigabytes of junk in just two clicks, and helps you maintain your Mac’s health.
You may want to check out more software for Mac, such as OS Cleaner Master, Uninstaller-OS Cleaner or OS Cleaner Pro, which might be similar to OS Cleaner.