Freeing up storage space: What can go?

In short: When the disk is full, an overview of the largest files, emptying the recycle bin and downloads, removing unused programs and moving photos and videos elsewhere help.

In more detail: An almost full drive makes systems slow and prevents updates. With systematic tidying you often win back many gigabytes without losing anything important. Make a backup first.

In Depth

Where the space goes

Use a storage analysis: Windows Settings → System → Storage, macOS About This Mac → Storage, Linux ncdu or du -h --max-depth=1. Tools such as WinDirStat or TreeSize show the largest folders graphically. Usually videos, photos, games, downloads and system files occupy the most space.

Tidying safely

• Empty the recycle bin, go through the Downloads folder.
• Disk Cleanup (Windows) removes temporary files and old update remnants.
• Uninstall programs and games you no longer use.
• Find and delete duplicate files (duplicate finder).
• Empty browser cache and apps’ offline data.
• Check old backups and restore points. Never delete system folders (Windows, System32, /usr) by hand.

Moving instead of deleting

Move photos and videos to the cloud or to an external drive/NAS. With OneDrive/iCloud there are files on demand (“Files on-demand”), which take up hardly any local space. Check that the backup sits in a second place before deleting originals.

Preventing

Keep at least 10 to 20 % free, especially with SSDs. Disable automatic media downloads in messengers, use streaming instead of local copies and check now and then. On the phone the settings’ storage management and deleting large chat histories with media help.

See also: Backup strategy, Using the recycle bin, SSDs