How to free up space on a Mac (safely)
Start with the files you won't miss: old installers (.dmg, .pkg), downloads you never opened, duplicates, big videos you can shrink, and caches that rebuild themselves. Then look at apps you don't use and developer files.
The safe wins first
- Open OneMacTools › Mac Clean Up. It scans Downloads, Desktop, Movies, Pictures, caches, logs and Applications.
- Review the cards: old installers, forgotten downloads, old screenshots, big videos, duplicates, look-alike photos, unused apps.
- Tick what to remove and click Move to Trash. For big videos and screenshots you can choose Shrink instead to keep them smaller.
- Empty the Trash when you're sure. Until then, History can put everything back.
Then the hidden space
System Data hides a lot. Mac Clean Up's System Data review shows leftovers from deleted apps and old device backups. AI Space shows what Cursor, Claude, ChatGPT and Ollama keep. Developers often find tens of gigabytes in old node_modules and build folders (Dev & Agents › Project Files).
What not to do
Don't delete files in /System or Library folders you don't recognise, and don't use “clean everything” buttons. Remove things one category at a time, so you know what went.
Do it with OneMacTools
Questions
How much free space should a Mac have?
Keep at least 10–15% of the disk free, or about 20 GB, so macOS has room for updates, swap and caches.
Does emptying the Trash free space immediately?
Yes. Files moved to the Trash still take space until you empty it.
