Not many techs recommend these 'Mac cleaning' apps. Just never trusted them to remove only what they should. Many reviewers noted that they often do
not delete everything, anyway. But, even worse, they sometimes delete files that are used by
other apps! You can easily delete most browser caches from their own menu. Many Apple apps have a "Debug" menu which usually includes that function. Many caches are simply rebuilt as soon as the app that needs them runs again, and, if it's the OS, they will probably get rebuilt as soon as you delete them! The cleaners claim deleting caches make you machine operate faster. It does... until it next needs the cache and things slow down while it gets rebuilt!
Unless you have a very old, small drive, it's hardly worth the risk of deleting the wrong stuff just to regain a few hundred bytes of disk space. If your drive is that small, it is probably pretty old and may be well beyond its 'mean time between failures'; in other words, run, do not walk, to get a replacement, and likely larger drive!
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Are there free or lower cost alternatives?
Besides the options built in to many apps, not to mention the "Un-installers", there a much better 'utility' apps that many of us here use; OnyX, Cocktail, Disk Warrior, TechTool Pro. I think only one of those is free, but they will all do so much more than "Clean My Mac".
If you do upgrade/buy it, first make absolutely sure you have a bootable, usable backup ...or
two!