How to Convert MOV to MP4 Without Losing Quality

MOV is what iPhones, Macs, and many cameras produce. MP4 is what almost every website, app, and Windows PC expects. Converting between them sounds like it should cost quality, but in most cases it does not have to. The trick is knowing the difference between remuxing and re-encoding.

Remux vs re-encode

MOV and MP4 are containers: wrappers around the actual video and audio. As we explain in MP4 vs MOV vs MKV vs WebM, the same H.264 or H.265 video can live in either one. That gives you two ways to convert:

If all you need is an MP4 that plays everywhere, remuxing is the right answer whenever it is possible.

Can your MOV be remuxed?

It depends on the codecs inside. MP4 supports fewer codecs than MOV:

To check, open the file's info: on a Mac, select it in Finder and press Command + I, then look under More Info for the codecs. In VLC on any computer, open the video and look at the codec information (Tools menu on Windows, Window menu on Mac). FFmpeg users can run ffprobe on the file.

Remuxing with FFmpeg

# Copy video and audio into MP4 without re-encoding
ffmpeg -i input.mov -c copy -map_metadata 0 -movflags +faststart output.mp4

• •-c copy copies the streams instead of re-encoding them, which is why it takes seconds.
• •-map_metadata 0 keeps metadata such as the recording date.
• •-movflags +faststart moves the index to the start of the file so it can play while downloading.
• •For H.265 from an iPhone, the file usually keeps its hvc1 tag, which Apple devices need. If an H.265 MP4 will not play on a Mac or iPhone, add -tag:v hvc1 to the command.

If FFmpeg stops with "codec not currently supported in container", your MOV contains ProRes video or PCM audio. Use one of the commands in the next section.

When you must re-encode

# PCM audio only: copy the video, convert the audio to AAC
ffmpeg -i input.mov -c:v copy -c:a aac -b:a 192k -movflags +faststart output.mp4

# ProRes video: re-encode to H.264 at high quality
ffmpeg -i input.mov -c:v libx264 -crf 18 -preset slow -pix_fmt yuv420p -c:a aac -b:a 192k -movflags +faststart output.mp4

Re-encoding only the audio keeps the video untouched, and AAC at 192 kbps is transparent for almost any listener. For ProRes, CRF 18 in H.264 is visually very close to the original while being a small fraction of the size; ProRes files are enormous by design. More on CRF values in CRF vs bitrate.

Without FFmpeg

• •Mac: iMovie and Final Cut Pro export MP4 (Share, then Export File). This re-encodes, at high quality by default. Note that QuickTime Player's Export As saves a MOV, not an MP4.
• •Windows: Clipchamp (built into Windows 11) exports MP4. HandBrake (free) converts MOV to MP4 with presets.
• •Online: the BoltCompress compressor converts MOV to MP4 while compressing. Pick MP4 as the output format.

Common questions after converting

• •The MP4 is the same size as the MOV: that is expected after a remux. The data inside did not change.
• •Colors look different: HDR iPhone video (Dolby Vision or HLG) can look washed out in players without HDR support. See the HDR note in how to compress 4K video.
• •The date or location disappeared: add -map_metadata 0, or check that your conversion app keeps metadata.

Summary

If your MOV contains H.264 or H.265 with AAC audio, which covers most phone videos, remux it and you get an identical MP4 in seconds. ProRes video and PCM audio cannot be copied into MP4, so re-encode those at high quality. Only compress when you also want a smaller file.