AppCleaner alternatives, and the one thing it cannot do

AppCleaner is the tool people recommend in one line, and the recommendation is correct. Drag an app onto it, it finds the files that app left around the system, you click delete. It is free, it is small, and there is no reason to look for a replacement for that job.

The limit is in how you use it, not in how well it works

AppCleaner starts from an application. You give it the app, it searches for the matching files. That is what makes it accurate, and it is also the whole limitation: it can only clean up after apps you still have installed. The moment you drag an app to the Trash the normal way, its support folders, caches, containers and preferences stay on disk with nothing left to point AppCleaner at.

That matters because of the order people actually do things in. Almost nobody installs AppCleaner first. It gets installed after a few years of trying software out, by which point the leftovers are already orphaned.

How much this is worth, measured

On the Mac these numbers were taken from, on 9 September 2026, the largest folders in ~/Library/Application Support were 6.3 GB for one browser and 3.0 GB for a single development tool, with an 853 MB folder from an app that had not been opened in months. Run the same check on yours:

du -sh ~/Library/Application\ Support/* 2>/dev/null | sort -h | tail -20

Read the list with one question in mind: for each name, is that app still in your Applications folder? The ones you cannot place are the orphans, and they are the space AppCleaner was never able to reach. The same check is worth running against ~/Library/Containers and ~/Library/Caches, which is where sandboxed apps put the same kind of thing.

The options, and what each is actually for

There is no need to choose one. Keeping AppCleaner for uninstalling, and something that reads the disk for the years of leftovers already there, covers both directions. If the tool you were comparing against is a subscription suite, the CleanMyMac comparison covers what those actually do.

Is AppCleaner safe

It is a long standing free app from a small developer, downloaded from the developer's own site, and it moves files rather than running anything privileged. The risk that matters is not the app, it is the confirmation dialog: any uninstaller shows you a list of matched files, and a match is a guess based on names and identifiers. Read the list before you confirm, particularly when a name is generic enough to belong to more than one thing.

That guessing is also why manual cleanup misses things. An app whose bundle identifier does not contain its own name leaves files that no name based search will find, which is covered in more depth in what uninstalling leaves behind.

Where Free Mac differs, and where it does not

It does not replace AppCleaner at the moment of uninstalling. What it does instead is start from the disk rather than from an app: every application totalled with the files it put elsewhere, and the folders whose owner is no longer installed listed as what they are. The scan and the map are free. Exact sizes, opening a folder and removing anything need a key at $19.99 every six months, and AppCleaner does its own job for nothing, so keep both.

If the folders you are looking at turn out to be caches rather than app data, what is in ~/Library/Caches explains which of them rebuild themselves and which do not.