How do I convert MOV to MP4 on a Mac?

Open this page in Safari, Chrome, or Firefox; drop your MOV file onto the tool; click Convert. The conversion runs locally on your Mac — no software install, no upload. The output is a standard MP4 ready for sharing.

Does this work for iPhone videos?

Yes. Modern iPhones record HEVC (H.265) video inside a MOV container. This tool wraps that same video stream into an MP4 container without re-encoding — instant, no quality loss. The resulting MP4 plays on any device that supports HEVC.

Will I lose any quality?

No. The default mode is a stream copy — FFmpeg lifts the encoded video and audio out of the MOV container and drops them into an MP4 container without touching the frames themselves. The output is bit-identical to the source in everything but the wrapper.

Is anything uploaded?

No. FFmpeg compiled to WebAssembly runs inside this browser tab. Open DevTools Network tab and confirm: no outbound request carries the file.

How long does it take?

For most MOV files, stream-copy mode finishes in seconds regardless of clip length — the work is reading the file and writing the container, not encoding video. Re-encode mode is slower because every frame is decoded and re-compressed.

Why might I need the re-encode option?

A handful of MOV files use audio or video codecs that MP4 does not officially support. In that case stream copy fails and the tool will prompt you to re-encode. Re-encode also produces H.264 MP4 with maximum compatibility for older devices that may not handle HEVC.

Is there a size limit?

No imposed limit. The practical ceiling is your browser memory. Multi-gigabyte files are possible if your machine has enough free RAM.

// Tools / MOV → MP4

Convert MOV to MP4 on Mac

Drop a QuickTime or iPhone MOV file and download an MP4 a few seconds later. The file never leaves your browser. Works on Mac, Windows, and Linux — no app to install, no account, no upload.

// MOV → MP4

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// Long read
Why MOV files keep showing up — and what to do about themWhat MOV actually is, why iPhones record to it, and the real reason converting to MP4 is almost always instant rather than a slow re-encode.
MOV is QuickTime, and QuickTime is closer to MP4 than you thinkMOV stands for QuickTime Movie. Apple created the container in 1991 for QuickTime, the multimedia framework that became the backbone of consumer video on Macs. The format was so successful that when the ISO standardised MPEG-4 video in the late 1990s, they used QuickTime's file structure as the starting point. The result is that MP4 and MOV are technically siblings — both based on the ISO base media file format, both organising data into the same kinds of blocks (called atoms in MOV, boxes in MP4).
That family resemblance is the reason MOV-to-MP4 conversion is almost always a no-op. The video and audio streams inside a MOV and inside an MP4 are usually the same — typically H.264 video and AAC audio. Switching containers is a clerical job: rename the structure, copy the streams, write a new index. FFmpeg does this in seconds even on hour-long source files, because no encoding work is involved. That is what the default mode of this tool does, and it is why the output has zero quality loss.
Why Macs and iPhones default to MOVOn macOS, MOV is the format the system writes when you record something with the built-in screen-recording tool, when you export from Final Cut Pro, when you save from Photo Booth, when you trim a clip in Photos. The choice is mostly historical — QuickTime was there first — but it persists because MOV supports a few Apple-specific features (multiple audio tracks with rich metadata, embedded metadata for editing apps, alpha-channel video in ProRes 4444) that MP4 historically did not.
iPhones are slightly different. Photos and Camera record MOV containers wrapping HEVC (H.265) video. The container is MOV because Apple has always used MOV; the codec is HEVC because it produces files about forty percent smaller than H.264 at the same quality. The MP4 container also supports HEVC, so converting an iPhone MOV to MP4 is again a container swap — the HEVC video stays untouched, just re-wrapped.
Where things actually go wrongMost MOV-to-MP4 conversions are trivial. There are three places they get less trivial.
Receiving device cannot play HEVC. If you convert an iPhone MOV to MP4 via stream copy, the result still contains HEVC video. iPhones, recent Macs, recent Windows, and modern smart TVs handle this. Older Android devices, older laptops, and older web browsers do not. If you are sending the clip to someone on uncertain hardware, enable the re-encode option above — it produces H.264 MP4 that plays anywhere.
Audio is in an unusual codec. A small number of MOV files contain audio in PCM, Apple Lossless, or some other codec MP4 does not officially support. FFmpeg refuses to wrap those into MP4 as a stream copy. The error message in the log will mention codec compatibility; the fix is to enable the re-encode option, which re-compresses both video and audio into MP4-friendly formats.
Apple-specific metadata is preserved differently.Some editing metadata (chapters, timecode tracks, certain colour-tag conventions) survive the MOV-to-MP4 hop only partially. For shipping clips to recipients, this is invisible. For professional editing workflows, you might want to keep the MOV and only convert when actually sharing.
Doing it on a Mac specificallyThe traditional Mac workflow for MOV-to-MP4 has been one of three things, none of them great. The first is QuickTime Player's "Export As" menu, which works for short clips but lacks codec control and is hidden behind a paid pro version for many features. The second is to install HandBrake, which is excellent but is a separate download and adds another piece of software to update. The third is to upload to a web-based converter, which works but requires sending your video to a stranger's server.
The tool on this page is a fourth option: a browser tab that runs FFmpeg locally. Nothing to install, nothing to upload, no QuickTime pro license required. The conversion uses the same FFmpeg engine that backs most professional video software, compiled to WebAssembly so it executes inside Safari, Chrome, or Firefox. The privacy guarantee is the strongest possible — there is no upload path for the data to take, full stop. If you want to verify, open Safari's Web Inspector or Chrome's DevTools, watch the Network tab while you convert, and confirm that nothing leaves.
What the output MP4 looks likeFor a typical iPhone MOV converted with the default settings:
File size — within a fraction of a percent of the source. Container overhead is negligible.
Video codec — whatever was in the source (HEVC for modern iPhones, H.264 for older ones), unchanged.
Audio codec — AAC, unchanged.
Faststart flag — enabled, which means the MP4 can begin streaming before the whole file is downloaded. Useful for web embeds.
Compatibility — universal for H.264 sources; modern devices for HEVC sources.
Frequently asked questionsWill Safari/Chrome/Firefox work?Yes on all three for desktop. Mobile Safari has historically restricted some of the WebAssembly features FFmpeg uses, so very large files may stall on iPhone. Desktop Safari, Chrome, and Firefox all work for clips up to several gigabytes.
Why does my file appear unchanged in Finder?The output is a real MP4 — check the extension. Some macOS previews show video thumbnails identically for MOV and MP4 because both wrap the same underlying video, and that is exactly right: the picture is the same, just in a different container.
Can I batch convert multiple MOVs?Not on this page — the tool handles one file at a time. If batching matters, install desktop FFmpeg and write a one-line shell loop. The browser vs desktop comparison covers when each option makes sense.
What about MOV to MP4 on Windows or Linux?The tool works identically on Windows and Linux. The page is framed for Mac users because MOV files originate from Apple hardware most of the time, but there is nothing macOS-specific about the implementation.
What about converting MP4 back to MOV?Use the MP4 converter — it does container conversions in both directions.
Where can I learn more about FFmpeg?The blog post how FFmpeg works is a non-technical overview of what FFmpeg actually does. For codec specifics — why HEVC files are smaller, what AV1 is — see video codecs explained.
I need other tools — where are they?On the tools hub.