MP4 converter

FileReshape's MP4 converter turns MOV, MKV, WebM, AVI, WMV, FLV, 3GP and MPEG videos into MP4 files with FFmpeg inside your browser. The video is not uploaded. When the picture is already H.264 or H.265 it is copied without quality loss in seconds; other videos are re-encoded to H.264, which takes minutes.

Drop your video file here or click to choose

Did a file not convert correctly? E-mail [email protected], ideally with a small sample file, and it will be fixed.

Key facts

Input: MOV (.mov). Output: MP4 (.mp4).
Your files are not uploaded: the work is done in your browser, on your own device.
File size: up to 2 GB per file (the limit of the browser's WebAssembly memory).
Needs a current browser (Chrome, Edge, Firefox or Safari) on a computer, tablet or phone; nothing to install.
Free to use, with no sign-up.

Why convert a video to MP4

MP4 is the format that every phone, TV, video editor, website and messaging app accepts. Videos arrive in many other wrappers: MKV from screen recorders and downloads, WebM from browser recordings and video calls, AVI and WMV from old cameras and Windows PCs, MOV from iPhones and Macs, MTS from camcorders. This converter reads the file in your browser with FFmpeg and writes an MP4. If the picture inside is already H.264 or H.265, it is copied into the new file without being decoded, which is fast and loses nothing; only the container changes. Other codecs, such as VP8, VP9, MPEG-4 Part 2 (DivX, Xvid) or WMV, are encoded again as H.264 so the MP4 plays everywhere. The sound is copied when it is AAC or MP3 and converted to AAC otherwise.

How to convert a video to MP4

Drop the video in the box, or click to choose it.
Check the codecs shown and choose whether to keep the video as it is or convert it to H.264.
Click Convert to MP4 and save the MP4 file.

What to know before converting to MP4

Copying or re-encoding

Copying the video stream takes seconds even for a long film and keeps the exact quality. Re-encoding to H.264 is needed for VP8, VP9, AV1, DivX, WMV and other codecs, and runs on your own processor: expect two to six minutes per minute of 1080p video on a recent laptop. The page shows the time left.

H.265 (HEVC) videos

iPhones and many cameras record H.265. Kept as it is, it plays on recent phones, Macs and Windows 11 with the HEVC extension, but some older TVs, editors and websites need H.264. Choose Convert to H.264 if the MP4 has to play everywhere; the file gets larger and the conversion takes longer.

Subtitles, chapters and extra sound tracks

The MP4 gets the first video and the first sound track. Subtitles, chapters and additional audio languages that an MKV may hold are left out; use a desktop program such as HandBrake or MKVToolNix if you need them.

Protected videos

Films from DVDs, Blu-rays and streaming apps are encrypted. They cannot be read here, and the tool only shows a message.

About the formats

MOV

MOV is Apple's QuickTime video format and what iPhones, iPads and Macs save screen recordings and many camera videos as. Inside is usually H.264 or H.265 (HEVC) video and AAC sound, the same as in an MP4, but some Windows programs, older TVs and websites do not accept the .mov extension.

QuickTime was released in 1991; MP4 was later built on its file structure.
iPhones record in HEVC (H.265) since iOS 11 when the camera is set to "High Efficiency".
Professional cameras use MOV with ProRes, a codec that keeps much more detail and makes very large files.

MP4

MP4 (MPEG-4 Part 14) is the most common video file format. Phones, cameras, YouTube, WhatsApp and every computer and TV use it. An MP4 is a container: the picture inside is usually compressed with H.264 or H.265 (HEVC) and the sound with AAC, and the same file can also hold subtitles, chapters and a cover image.

The format was standardised in 2003 and is based on Apple's QuickTime format, which is why MP4 and MOV files are so alike.
H.264 video with AAC sound plays on practically every device made in the last 15 years.
A minute of phone video in 1080p is typically 100–200 MB; in 4K it is often 350–500 MB.
The "faststart" layout puts the index at the beginning, so a video can start playing before it is fully downloaded.

Frequently asked questions

Is my video uploaded?

No. The conversion runs in your browser with FFmpeg compiled to WebAssembly. The engine (32 MB) is loaded once from the jsDelivr network; your video stays on your device.

Does converting to MP4 reduce the quality?

Not when the video is copied: the picture is the same, bit for bit. Re-encoding to H.264 uses a high quality setting, so the difference is hard to see, but the file can become larger or smaller than the original.

Which formats can I convert?

MOV, MKV, WebM, AVI, WMV, FLV, 3GP, MPEG, TS, MTS and M2TS, and MP4 files with codecs that do not play everywhere. Very old or unusual codecs may not be supported by FFmpeg's browser build.

How large can the video be?

Files up to 2 GB can be opened, because the video is read in pieces from your disk. The converted MP4 must fit in the browser's memory.