Is it safe to delete iMovie libraries?
An iMovie library: the video and photos you imported, your projects, and render files iMovie creates.
Review first
It's your own data, or hard to recreate. Decide item by item.
~/
- Never inside ~/
Library
What it is
iMovie keeps each library as a single package, by default named iMovie Library in your Movies folder. It holds the clips and photos you imported into events, your movie and trailer projects, and the render files iMovie creates. It grows with every clip you import. Render files can be deleted in iMovie settings; everything else is your own media and edits.
If it's removed
Deleting render files removes no imported media, but iMovie renders again when needed, so exports may take longer. A library on an external drive is available only while the drive is connected.
What to do instead
In iMovie, choose iMovie > Settings, then click Delete next to Render Files. You can also delete events and projects you no longer need in iMovie, or move the library to an external drive as Apple Support describes.
The free analyzer finds it and explains it, with these steps. The app doesn't remove it for you.
Sources
- support.apple.com/guide/imovie/change-imovie-settings-mov756ac27d8/mac
- support.apple.com/en-us/102186
Last checked on 26 Sep 2026. Every entry is written and checked by hand; the app and the command-line tool use the same words.