What is inside a MOV file?
MOV is Apple's QuickTime container. The extension tells you how the video is packaged, not how it is compressed. An iPhone .mov usually contains HEVC (H.265) video; a Mac screen recording usually contains H.264 at your screen's full resolution; files from professional cameras or editors may contain ProRes, which is very large by design. That is why two MOV files of the same length can differ in size by ten times or more.
This tool reads the MOV, re-encodes the video to H.264 at the resolution and quality you choose, and writes an MP4. MP4 plays on nearly every device and website, which also solves the common problem of Windows or Android users being unable to open a .mov you sent them.
How to compress a MOV file
- Drag the .mov file onto the tool above, or tap “Choose video”. Nothing is uploaded.
- Keep the default Medium quality at 1080p, or pick High for footage you want to archive.
- For a strict limit, switch to Target size and type the number of megabytes you need.
- Press Compress video, compare the sizes, and download the MP4.
Best settings by source
- Mac screen recordings: 1080p or 720p, Medium quality. Screen content is mostly static, so it compresses extremely well and text stays readable.
- iPhone videos (HEVC): HEVC is already efficient, so the biggest saving comes from 4K → 1080p. See reduce iPhone video size.
- QuickTime exports and camera footage (H.264): High quality at 1080p usually saves a lot with little visible change.
- ProRes masters: work in shorter sections or use desktop software; browser memory is limited.
MOV vs MP4: which should I use?
For editing on a Mac, MOV is perfectly fine. For sharing, MP4 is the safer choice: it is supported by every major browser, Windows' built-in player, Android, social networks and email previews. Since both containers can hold H.264 video, converting to MP4 does not by itself lower quality — the size reduction comes from the re-encode settings you choose.
Compressing Mac screen recordings for sharing
Screen recordings made with ⇧⌘5 or QuickTime capture every pixel of a Retina display, often at very high bitrates. For a tutorial or bug report, that is far more than needed. Choose 1080p (or 720p for small windows), keep Medium quality, and you will typically end up with a file that is easy to attach to an email, a support ticket or a Slack message. If you need an exact size, the email preset and 10 MB preset do the maths for you.
Troubleshooting
- The file will not load: very large ProRes or unusual codecs may not decode in the browser. Export a standard H.264 version from QuickTime (File › Export As) and try again.
- The browser tab crashes: close other tabs, lower the resolution, or compress a shorter section.
- HDR footage looks flat: HDR is converted to standard dynamic range MP4, which can look less vivid.
Already have an MP4? Use compress MP4.