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How to Convert MOV to MP4 on Mac, Windows, and Linux

Your Mac records in MOV. The rest of the world expects MP4. Here's how to convert without re-encoding (fast) or with compression (smaller), entirely on your machine.

Why MOV files are a problem

MOV is Apple's container format. It works great in the Apple ecosystem — QuickTime, iMovie, Final Cut. But when you try to share a MOV file with someone on Windows, upload it to a website, or embed it in a presentation, you'll often hit compatibility issues. MP4 is the universal standard.

The good news: MOV and MP4 are both container formats. The actual video codec inside is often the same (H.264 or H.265). In many cases, converting is just repackaging — no quality loss and near-instant.

Fast conversion (remux, no quality loss)

convx convert recording.mov --to mp4

If the video codec is already H.264/H.265, ConvX detects this and remuxes instead of re-encoding. The conversion takes seconds regardless of file size because it's just repackaging the data into a new container. Zero quality loss.

With compression (smaller file)

convx convert recording.mov --to mp4 -q 75

If you need a smaller file, lowering the quality triggers a re-encode. Quality 75 produces a visually identical file at roughly 40-60% of the original size.

Screen recordings from Mac

Mac's built-in screen recorder (Cmd+Shift+5) saves as MOV. These files are often huge because they use Apple's ProRes or high-bitrate H.264. Converting to MP4 with compression can reduce a 500MB screen recording to under 50MB:

convx convert "Screen Recording 2026-02-20.mov" --to mp4 -q 70

iPhone videos

When you AirDrop a video from your iPhone to your Mac, it arrives as MOV. If you need to share it on Slack, Discord, or email, convert it first:

convx convert IMG_1234.mov --to mp4

Batch convert a folder

convx convert "./videos/*.mov" --to mp4 -j 4 -d ./converted

Converts every MOV file in the folder using 4 parallel jobs.

Auto-convert as files arrive

convx watch ~/Downloads --to mp4 --filter "*.mov"

Every MOV file that lands in your Downloads folder gets automatically converted to MP4. Useful if you regularly AirDrop videos from your phone.

Using the desktop app

Drag your MOV file into ConvX, select MP4 as the output format, and click convert. The app will automatically detect if it can remux (fast, no quality loss) or if it needs to re-encode.

MOV vs MP4: what's the difference?

Both MOV and MP4 are container formats — they wrap video, audio, and metadata into a single file. The actual video quality depends on the codec (H.264, H.265, ProRes) and settings used, not the container. MP4 has wider compatibility, which is why it's the better choice for sharing.