Convert · runs on your device

Convert MP4 to MOV in your browser

MP4 and MOV are both ISO base media files, so Video Mender simply rewrites the container: your MP4 becomes a QuickTime MOV in seconds with the video and audio streams copied bit for bit.

Nothing is uploaded

Drop video files here

MP4 · M4V

Choose video files to convert

Output format

Native on macOS and iOS; Windows and Android players are inconsistent.

Video codec

The universal baseline. Hardware decoding exists on essentially every device sold since 2010.

How to size the output

A constant quality target. File sizes vary with how demanding the footage is.

Quality — 10 of 10

Resolution limit

Files smaller than the limit are left alone. Capping usually looks better than lowering the bitrate.

Frame rate

Audio

Fast rewrapCopy streams without re-encoding when the codecs already fit

Lossless and near-instant when it applies. It cannot reduce file size, so turn it off if you need a smaller file.

This is the cleanest conversion on the site. QuickTime MOV is where the MP4 specification came from, and the two formats store frames in almost the same way. Changing one to the other means rewriting a small amount of structural metadata and copying the media streams across untouched.

People usually need MOV for one of two reasons: a piece of Apple software insists on it, or a workflow was built around QuickTime years ago and never changed. Either way you should not pay a quality penalty for a container preference, and here you do not.

Because nothing is re-encoded, the MOV comes out the same size as the MP4 went in, and the whole job finishes at file-copy speed even for large files.

What this actually does to your file

Rewrap or re-encode

Rewrap runs for H.264, HEVC and MPEG-4 video with AAC or MP3 audio, which covers virtually every MP4 in existence. MOV additionally accepts uncompressed PCM audio, so nothing in a normal MP4 blocks the copy.

Quality

On the rewrap path there is no quality change at all, because no frame is decoded. Only a deliberate resolution cap or quality change forces a re-encode.

A rewrapped MOV holds the same H.264 or HEVC video as the MP4. It is not ProRes, and converting will not turn a delivery file into an editing master.
The file size does not change, because the compressed data is identical.
If your software specifically demands ProRes or DNxHD, this conversion will not satisfy it — that needs a codec this build does not encode.

How to use this page

Add MP4 or M4V files to the queue.
Keep the output as MOV and leave fast rewrap enabled.
Press Start — expect seconds, not minutes.
Download the MOV files individually or as a ZIP.

Where the result plays

Checked against the containers and codecs this page produces, stated conservatively.

Target	Works	Detail
macOS and iOS	Yes	MOV is the native QuickTime format and opens everywhere on Apple platforms.
Final Cut Pro	Yes	Imports MOV directly; this is the usual reason for the conversion.
Windows	Partly	Modern Windows plays H.264 in MOV, but some older software still expects MP4.
Browsers	Partly	Safari plays MOV inline. Chrome and Firefox usually download it instead.

The formats involved

Format	Read	Write	What it is
MP4	Yes	Yes	The MPEG-4 Part 14 container. It is a wrapper, not a codec — an MP4 usually holds H.264 or HEVC video with AAC audio.
M4V	Yes	Yes	Apple's MP4 variant used by iTunes. Byte-for-byte it is an MP4; the extension exists so iTunes can flag optional FairPlay DRM.
MOV	Yes	Yes	Apple QuickTime. Structurally a close cousin of MP4, which is why MOV files can often be rewrapped to MP4 with no re-encode.

Tested limits

Real ceilings measured on real devices, not a marketing claim of unlimited.

Limit	Desktop	iPhone / iPad	Why
File size — rewrap	1.3 GiB	384 MiB	Rewrapping never decodes a frame, so it tolerates far larger files.
File size — re-encode	1.0 GiB	256 MiB	Decoding holds uncompressed frames in memory, which is the real constraint.
Clip length — re-encode	4:00:00	30:00	Beyond this, progress reporting and memory behaviour stop being dependable.
Resolution — re-encode	4096 × 2160	1920 × 1080	A 4K frame is about 12 MB decoded, before the encoder allocates anything.

If something goes wrong

Final Cut still will not import the MOV.

Final Cut is objecting to the codec, not the container. If the source is HEVC or an unusual H.264 profile, re-encode to H.264 by turning fast rewrap off and choosing the High quality preset.

The MOV is exactly the same size as my MP4.

That is the expected result of a rewrap and a sign it worked. The compressed streams were copied without change.

Can I get a smaller MOV?

Turn fast rewrap off and pick a quality preset or a target size. That re-encodes the video, which is the only way to make it meaningfully smaller.

Your video never leaves this device

This is a structural property of the application, not a policy we ask you to take on trust. There is no upload endpoint, no API route and no server action anywhere in the codebase, so there is nowhere for a video to be sent even by mistake.

Conversion runs in WebAssembly inside this browser tab. The engine is served from this domain and loaded only when you start a job.
The Content-Security-Policy restricts network connections to this origin, so the page is not permitted to contact a third party at all.
Nothing is stored. Close the tab and every queued file and finished output is gone — which is also why you should download results before you leave.
There are no accounts and no AI. Anonymous page views are counted — which page, roughly what country, what kind of device — and nothing whatsoever about your files.

The repository contains a test that fails the build if any media byte is passed to fetch, XMLHttpRequest, sendBeacon or a WebSocket. See the privacy page for how that is verified.

Questions

Is MOV better quality than MP4?

No. Quality lives in the codec, not the container. A rewrapped MOV contains exactly the same H.264 or HEVC frames as the MP4 did, so the two files look identical.

Why is this conversion so much faster than MP4 to WebM?

Because MOV can carry the codecs MP4 already uses, so the frames are copied rather than re-compressed. WebM accepts none of those codecs, which forces a full re-encode.

Does converting to MOV give me ProRes?

No. ProRes is a codec that happens to live in MOV files. Rewrapping keeps your existing H.264 or HEVC video; this build does not encode ProRes.

Will the MOV play on Windows?

Usually yes on current Windows versions, since the video is H.264. Very old Windows software may still prefer the MP4, so keep it if in doubt.

Can I batch-convert an entire folder?

Yes. Because rewrapping is cheap, large batches of MP4 to MOV finish quickly, and you can download the results sequentially or as a single ZIP.