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An MP4 video is more than a stream of pictures and sound. Around the media sit boxes that record where the clip was shot, which device recorded it, when, what software touched it and sometimes a whole track of sensor readings. An MP4 metadata remover copies the video and audio into a new file and leaves those boxes behind. Nothing is decoded or re-encoded, so quality cannot change. Add an MP4 above, read what it contained and download the clean copy. MP4 files are processed on our server and deleted within minutes.
How an MP4 file is organised
MP4 is built from boxes, each with a four-character type and a length. Boxes nest inside each other, and most of the personal data sits in a few of them.
| Box | What it holds | In the clean file |
|---|---|---|
ftyp | The file type and compatible brands | Kept |
mdat | The compressed video and audio, called the media data | Kept, bit for bit |
moov | The index: how to find and play each sample | Rebuilt for the copied tracks |
mvhd, tkhd, mdhd | Creation and modification times, durations, track settings | Times written as empty; durations and settings kept |
udta and meta with ilst | Tags such as title, artist, comment, date and encoder | Removed |
©xyz inside udta | The GPS position as text, for example +37.7749-122.4194/ | Removed |
mdta keys in meta | Device and software details, such as an Android version | Removed |
| Handler names and track titles | Names of tracks, such as “VideoHandler” | Removed, then reset to plain defaults |
| Timed metadata and telemetry tracks | GPS, speed and sensor readings stored as extra tracks | Removed |
uuid | XMP editing history, Content Credentials (C2PA) | Removed |
| Chapters | Chapter names and times | Removed |
free, skip | Padding | Left behind |
Video, audio and subtitle tracks are copied. Anything that is not one of those three kinds of track is not.
Where the personal data comes from
- Android phones commonly write the GPS position into the
©xyzbox, and often tags with the operating-system version and the capture frame rate. - Action cameras such as GoPro record a telemetry track with GPS, acceleration and gyroscope readings alongside the video.
- Drones and dashcams store flight or driving data in extra tracks or sidecar files, depending on the model.
- Editors and encoders write their name and version, and sometimes an XMP packet with project details.
- Screen recorders and conferencing tools add the application name and a creation time.
What stays, and what we noticed in testing
We built MP4 files with a standard encoder and a metadata writer, cleaned them with the production code, and compared the streams with and without the cleaning. The video and audio streams were bit-identical in every case.
- A file with a title, a location tag, track titles, chapters and an XMP box: every one gone, and the report showed nothing left.
- Two audio tracks: both kept, in order. Language codes such as
engandfraare kept, because they say nothing about a person and players use them to choose a track. Track titles are removed. - Text subtitles: kept, with their language code, and without their title.
- A fragmented MP4 of the kind used for streaming: cleaned, plays normally, video stream identical.
- Cover art: a picture stored in the file as a second video track is kept as it is. Check that picture yourself, because it may carry its own data.
- Rotation: kept, so portrait clips stay upright.
Some software encoders also write their own name and settings inside the compressed stream. x264, for example, puts a settings string into H.264 video. That is part of the stream, and removing it would mean re-encoding, so it stays. It identifies the encoder, not you.
File names and dates on your disk
The clean copy is a new file. It is named after the original with “-clean” added, and your computer gives it today as its modified date. Neither of those is metadata inside the video, and neither changes the cleaning, but a file called beach-house-lahore.mp4 still says where it was filmed. Rename it before you send it.
Playing the clean file on the web
FFmpeg writes the index (moov) after the media data by default, and our output follows that, as the box order ftyp free mdat moov in a cleaned file shows. Players and web servers handle that fine, but a browser has to fetch the end of the file before it can start playing, which is slow on a basic server. If you will put the clip on your own web page, move the index to the front with one more copy step, which does not re-encode anything:
ffmpeg -i clean.mp4 -c copy -movflags +faststart web.mp4Clean an MP4 in four steps
- No account needed to start. Guests can clean 3 videos a month, a free account 10.
- Add the MP4. Drag it anywhere on the page or choose it. The upload shows its progress.
- Wait a few seconds. The server copies the tracks into a clean file and scans the result.
- Download and read the report. It lists the tags found and how many remain. Verified clean appears only when none do.
| Plan | Largest file | Videos a month |
|---|---|---|
| Guest, no account | 25 MB | 3 |
| Free account | 25 MB | 10 |
| Starter | 100 MB | 100 |
| Pro | 500 MB | 1,000 |
| Business | 1,000 MB | 10,000 |
For a clip bigger than your plan allows, run the same operation yourself with FFmpeg:
ffmpeg -i input.mp4 -map 0:v -map 0:a -dn -map_metadata -1 -map_metadata:s:v -1 -map_metadata:s:a -1 -map_chapters -1 -c copy -fflags +bitexact clean.mp4-map 0:s? if you need them.Check the result yourself
ffprobe -v error -show_entries format_tags:stream_tags -of json clean.mp4
exiftool -a -G1 -s clean.mp4language, and default handler names such as VideoHandler and SoundHandler, which FFmpeg writes itself. There should be no location, make, model, title, comment or creation_time.The video metadata remover page explains the whole tool for MP4, MOV, MKV and WebM, and the MOV page covers iPhone and QuickTime files. For several clips at once, the API and the MCP server work on whole folders.
Frequently asked questions
Does cleaning an MP4 reduce video quality?
No. The video and audio are copied without being decoded or re-encoded, and in our tests the cleaned streams were bit-identical to the originals.
Is my MP4 uploaded?
Yes. Video needs FFmpeg, so the file is uploaded over HTTPS to our server. The original is deleted as soon as cleaning finishes, the clean copy is deleted within 15 minutes, and we never open the content.
Does it remove the GPS location from an Android video?
Yes. The ©xyz position box and location tags are removed, and so are separate telemetry tracks stored in the file.
Will it remove the date the video was recorded?
Yes. Tag dates are removed and the creation and modification times in the file headers are written as empty. A date shown in the picture or in the file name stays.
Why did my language and subtitle labels change?
Language codes are kept. Track titles and handler names are removed, so a track called “English commentary” becomes an untitled track with the language eng. Subtitle tracks are kept.
Does it remove the cover picture inside an MP4?
No. Cover art stored as a picture track is copied as it is. If the picture itself carries personal data, replace it before cleaning.
Why can I still see an encoder name in the file?
Some encoders write their name and settings into the compressed stream. A stream-copy cleaner cannot change that without re-encoding, and it identifies software, not you.
Will portrait videos stay upright?
Yes. The rotation setting is kept.
Why does the clean MP4 start slowly on my website?
The index sits at the end of the file. Run the copy command shown above with -movflags +faststart to move it to the front without re-encoding.