How to Convert MOV to MP4 Without Uploading It (2026)
Your iPhone shoots beautiful video, then saves it as a MOV that your friend's Android phone or that upload form refuses to open. Here is what MOV actually is, and how to turn it into a universal MP4 in seconds, in the browser, usually with zero quality loss and nothing uploaded.
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The MOV that would not play
You film something on your iPhone, AirDrop or send it to someone, and they reply: “it will not open.” Or you go to upload it to a site and the form only accepts MP4. The file ends in .mov, and suddenly your perfectly good video is stuck. It is one of the most common, most annoying little friction points in sharing video.
The good news: converting MOV to MP4 is usually trivial, and you do not need to upload your video to anyone. A browser can do it on your own device, and in the most common case it is near-instant with no loss of quality at all. Here is why, and how.
What MOV actually is
MOV is Apple's QuickTime file format. When you record video on an iPhone, iPad or Mac, it is often saved as a MOV. It is a perfectly good, high-quality format, and it plays flawlessly across the Apple ecosystem. The problem is simply reach: Windows' built-in players, many Android phones, and a lot of websites and apps expect MP4 and may stumble on MOV.
Container vs codec: the key idea
Here is the insight that explains everything. A video file has two separate parts: the codec, which is how the actual picture is compressed, and the container, which is the wrapper that holds the video, the audio, and the metadata together. MOV and MP4 are both containers. The codec inside an iPhone MOV is very often H.264, which is exactly the codec MP4 uses too.
So in the common case, converting MOV to MP4 does not mean re-compressing the video at all. It means taking the same H.264 video and audio and putting them into an MP4 wrapper instead of a MOV wrapper. That is called remuxing, and it is the reason the conversion can be instant and lossless.
Got a MOV right now? Drop it in and watch it rewrap to MP4 in a blink.
Open the Convert Video toolHow to convert MOV to MP4 in your browser
- Drop your MOV. Open the Convert Video tool and drag your .mov file onto the page. It is read locally, never uploaded.
- Choose MP4. MP4 is selected by default for a MOV source. It is the universal, plays-everywhere choice.
- Convert. If the MOV is H.264, the stream is rewrapped into MP4 in a blink. If not, it is re-encoded to H.264 with WebCodecs.
- Download. Save your MP4. It will open on Windows, Android, the web, and everywhere else.
Why it is usually instant
Because most MOV files from iPhones already carry H.264 video, there is nothing to re-encode. SammaPix copies the existing video and audio packets straight into a fresh MP4 container. No frames are decoded and re-compressed, so there is no quality loss and the whole thing finishes almost instantly, even for a multi-minute clip. Compare that to a typical online converter, which uploads the entire file, queues it, transcodes it on a server, and makes you download it back.
A note on HEVC iPhone videos
Newer iPhones can record in HEVC, also called H.265, to save space. HEVC is more efficient, but its playback support outside Apple devices is patchier. If your MOV is HEVC and you want it to play truly everywhere, the safest path is to re-encode it to H.264 MP4. That is a real transcode, so it takes a little longer than a simple rewrap, but SammaPix still does it locally in your browser with nothing uploaded.
AVI, MKV and WebM to MP4 too
MOV is the most common case, but the same tool handles the others. MKV files with H.264 rewrap to MP4 just as instantly. Older AVI files and WebM (VP8/VP9) use codecs MP4 does not accept, so they are transcoded to H.264 on the way. And if you need to go the other direction, the tool also converts MP4 to WebM for the web.
| Source | To MP4 |
|---|---|
| MOV (H.264) | Instant rewrap, no quality loss |
| MKV (H.264) | Instant rewrap, no quality loss |
| MOV (HEVC) | Transcode to H.264 |
| AVI / WebM | Transcode to H.264 |
MOV, MKV, AVI or WebM, all to MP4 in your browser, nothing uploaded.
Convert a video nowWhy no upload matters
Personal videos are personal. They show your home, your family, your work. The moment you upload one to a free converter, you are trusting that company with the footage and trusting that they delete it. Browser-side conversion removes that question entirely: with SammaPix the file is read by code running on your own device, never transmitted, never stored. It is the same principle behind every SammaPix tool, explained more in the guide to browser-based privacy tools.
Convert MOV to MP4, no upload
Instant for H.264, lossless rewrap, all in your browser.
Open Convert VideoFAQ
How do I convert MOV to MP4 without uploading it?
Use a browser-based converter that runs locally. SammaPix's Convert Video tool at sammapix.com/tools/convert-video reads your MOV and, when it already contains H.264 video (which most iPhone MOV files do), rewraps it into an MP4 container almost instantly with no re-encoding and no quality loss. Everything happens on your device, so nothing is uploaded.
Why won't my MOV file play on Windows or Android?
MOV is Apple's QuickTime container. It is fully supported on iPhone, iPad and Mac, but Windows apps, Android phones and many web upload forms expect MP4. The video inside is often the same H.264 codec; it is just wrapped in a container those platforms do not always accept. Converting to MP4 fixes that.
Does converting MOV to MP4 reduce quality?
Usually not at all. When the MOV already uses H.264, SammaPix copies the video stream straight into an MP4 container without re-encoding, so the result is byte-for-byte identical in quality. Re-encoding only happens if the source uses a codec that MP4 does not accept, and then a high-quality setting is used.
Is it really instant?
For the common case (an iPhone MOV with H.264 video) it is near-instant, because no frames are re-encoded; the existing video and audio are simply placed into an MP4 wrapper. A several-minute clip can convert in well under a second.
What about iPhone videos in HEVC?
Some newer iPhones record in HEVC (H.265). HEVC can sit inside an MP4, but for the widest compatibility SammaPix can re-encode it to H.264 MP4, which plays on every device. That conversion is a true transcode and takes a bit longer than a simple rewrap, but still runs locally with no upload.
Is my MOV file uploaded to a server?
No. SammaPix converts the file entirely in your browser using the WebCodecs API. Your video is never sent to a server, stored, or seen by anyone. That is faster than upload-based converters and fully private.
Can I convert other formats to MP4 too?
Yes. The same tool converts AVI, MKV and WebM to MP4, and can also convert MP4 to WebM. MOV and MKV with H.264 rewrap instantly; formats with incompatible codecs are transcoded to H.264.
