Video is usually the single biggest use of storage on a Mac. A few minutes of 4K footage from an iPhone can be several gigabytes. For most everyday viewing, a smaller copy looks almost identical and takes a fraction of the space.
Understand the trade-off
Two things make the biggest difference to file size:
- Resolution. 4K has four times as many pixels as 1080p. If you mostly watch videos on a laptop or phone, 1080p is often plenty.
- Codec. HEVC (also called H.265) produces smaller files than H.264 at similar quality. Recent Macs and iPhones play HEVC smoothly; some older devices and websites do not.
Compression always discards some information. Keep the original of anything important until you are happy with the smaller version.
Method 1: Encode Selected Video Files (Finder)
This built-in option is the quickest way to shrink one or more videos.
- In Finder, select one or more video files.
- Right-click and choose Encode Selected Video Files. (On some versions it is under Quick Actions or Services.)
- Choose a Setting, such as 1080p, and choose HEVC for smaller files or H.264 for maximum compatibility.
- Click Continue. New files are created next to the originals; the originals are not changed.
Method 2: QuickTime Player
- Open the video in QuickTime Player.
- Choose File > Export As and pick a resolution such as 1080p or 720p.
- If offered, tick Use HEVC for a smaller file.
- Save the new copy.
QuickTime only offers resolutions equal to or smaller than the original.
Method 3: Photos
For videos in your Photos library:
- Select the video and choose File > Export > Export 1 Video.
- Choose a smaller Movie Quality, such as 1080p or 720p.
- Export to a folder, check the result, and import it back if you want to replace the original in your library.
Remember that deleting the original from Photos moves it to Recently Deleted, where it keeps using space until it is removed or 30 days pass. If you use iCloud Photos, deleting it also removes it from your other devices.
Method 4: iMovie
iMovie gives more control, and is useful if you also want to trim clips. Add the video to a project, then choose File > Share > File and pick a resolution and Quality. Lower quality settings produce smaller files.
Third-party tools
HandBrake is a long-standing free, open-source video converter with detailed control over quality and codec settings. Download it only from its official website.
Check before you replace
Watch the smaller copy all the way through, ideally on the screen you normally use. Pay attention to fast motion, dark scenes and fine detail like text, which show compression artefacts first. Then decide whether to keep the original, archive it to an external drive, or delete it.
Frequently asked questions
What is the best format to compress video on a Mac?
HEVC (H.265) gives the smallest files for a given quality and plays well on recent Apple devices. Choose H.264 if you need the video to play on older devices or upload to services that do not support HEVC.
Does compressing a video reduce its quality?
Yes, some detail is always lost, but at sensible settings such as 1080p HEVC the difference is often hard to see on a laptop or phone screen. Compare before replacing the original.
How do I make a video smaller to email?
Export it at a lower resolution, such as 720p, using QuickTime Player or Encode Selected Video Files. For large videos, sharing a link with iCloud Mail Drop or a cloud storage service often works better.
Want this done for you?
spacerecover lists your largest videos first, estimates what each quality setting would save, and makes a smaller copy on your own Mac. You watch it side by side with the original before anything is replaced, and the original is kept until you approve.