Make a video file smaller on a Mac with tools already installed
QuickTime, Finder and a built-in command can all shrink a video, often to a quarter of its size. Which to use, what quality you lose, and how to check it.
A 3 GB screen recording, a 4K clip you only need to email, a folder of old camcorder files. Your Mac can make all of them much smaller without any extra app. The only question is how much quality you are willing to trade.
1. Finder: the quickest
Select one or more videos in Finder, Control-click and choose Encode Selected Video Files. Pick a size, for example 1080p, and choose HEVC for the smallest files. The new files are saved beside the originals.
2. QuickTime Player: pick a resolution
Open the video in QuickTime Player, then File, Export As, and choose 1080p, 720p or 480p. Lower resolution means a smaller file. Good for sharing a clip quickly.
3. Terminal: for batches
macOS includes a command called avconvert. Run avconvert --help to list its presets. For example:
avconvert --source input.mov --output smaller.mov --preset PresetHEVC1920x1080What to expect
| From | To | Typical saving |
|---|---|---|
| 4K H.264 | 1080p HEVC | 70 to 90 percent |
| 1080p H.264 | 1080p HEVC | 30 to 50 percent |
| Screen recording | 1080p HEVC | Often 50 percent or more |
| Already HEVC at the same size | HEVC | Little or none |
Compare the result:
ls -lh input.mov smaller.movKeep the quality you need
- Watch the compressed version on a big screen before deleting the original.
- For anything you might edit later, keep the original on an external drive rather than deleting it.
- Compressing an already compressed file again loses quality each time. Always start from the original.
Why the originals are so big in the first place: 4K video storage per minute. Other ways to squeeze files: compressing files to save space.
Related: HandBrake's folders.
Common questions
How do I compress a video on a Mac for free?
Select it in Finder, Control-click, choose Encode Selected Video Files, and pick a resolution with HEVC. QuickTime's File, Export As also works.
How much smaller can I make a video?
Converting 4K H.264 to 1080p HEVC often saves 70 to 90 percent. Converting a file that is already HEVC at the same size saves little.
Does compressing a video lose quality?
Some, especially at lower resolutions. Check the compressed file before deleting the original, and keep originals you may edit later.