“Your disk is almost full”: what to do
macOS shows this warning when free space gets very low. Here’s what it means and how to fix it quickly and safely.
Why it matters
macOS needs free space to work: for virtual memory when apps use a lot of RAM, for app and system updates, and for temporary files. When space runs out, your Mac slows down and updates can fail.
A common rule of thumb is to keep at least 10 to 15% of your disk free.
Quick fixes, fastest first
- Empty the Trash.
- Delete installers (.dmg, .pkg) from Downloads.
- Remove old iPhone and iPad backups in Finder.
- Clear caches of apps you aren’t using.
- Use the recommendations in System Settings, General, Storage.
Stop it from coming back
The warning usually returns because the same things pile up again. Roomy’s Autopilot clears them every day and steps in right away when free space drops below 10%.