Media info
See what is actually inside a video or audio file — codec, resolution, bitrate, length.
The page to open when something will not play, or will not upload, and nothing says why. The length, the resolution and the average bitrate come from your browser and appear immediately. The codec, the channel layout and the per-stream bitrates need the video engine, which is a large download — so that is a second button rather than something this page does before you have asked.
How it reads a file
Nothing is decoded for the first table. The file is opened in a hidden video or audio element of your own browser with preload set to metadata, which reads the header and stops, so the length and the picture size appear at once even for a large file. The average bitrate is worked out from those two: the file size in bits divided by the length. It counts the sound and the container along with the picture, and it appears only for a video whose length the browser could read.
Read the technical details loads ffmpeg.wasm, the video engine, a 10 MB download your browser keeps for next time, and runs ffmpeg -i on the file. Its report becomes a table with a row for each stream (video, audio, subtitles or other) giving the codec name, frame size, frame rate, sample rate, channels and bitrate wherever ffmpeg states them. The container line under the table is ffmpeg's name for the format family, which is why an MP4 shows as mov,mp4,m4a,3gp,3g2,mj2.
Limits
One file at a time, up to 500 MB: MP4, MOV, AVI, MKV, WebM and 3GP video, and MP3, WAV, OGG, M4A, AAC, FLAC, Opus and WebM audio. The first table depends on your browser being able to open the file. Chrome does not open AVI, for example, so the length reads Not stated and there is no resolution, while the technical details still work: ffmpeg reads far more than any browser plays. The codec column gives the codec's name only, without its profile, and colour, HDR and rotation are not shown. A stream's own bitrate appears only where the file records one, which many MKV and WebM files do not. Nothing here changes the file, and the report is not a download: copy what you need from the table.
How to use it
- Add the video or audio file.
- Read the basics, which appear straight away.
- Press Read the technical details if you need the codecs as well.
Why use this tool
Completely private
Everything runs inside your browser. Your files and text are never sent to a server.
Free, with no limits
No sign-up, no watermarks and no cap on how many times you can use it.
Instant results
There is no upload or queue to wait for, so results appear as fast as your device can work.
Works on any device
Runs in any modern browser on phone, tablet or desktop. Nothing to install.
Frequently asked questions
- Why is the container listed as mov,mp4,m4a,3gp,3g2,mj2?
- That is ffmpeg's name for one family of formats, not a list of what is in the file. MP4, MOV, M4A and 3GP share a structure and one reader. The rows above it are where files differ: H.264 or HEVC, AAC or Opus.
- Is the average bitrate the video's bitrate?
- Not quite. It is the whole file divided by its length, so the sound and the container are in it too. The video row in the technical details shows the picture's own bitrate when the file records it.
- Why are the length and resolution missing for my AVI or MKV file?
- The first table comes from your browser, and not every browser opens every format: Chrome does not open AVI at all. Press Read the technical details. ffmpeg reads the file directly, and its table gives the resolution, frame rate and codecs.
- Why are the codecs behind a second button?
- Because only the video engine can read them, and loading it is a 10 MB download. Duration, resolution and file size come from your browser for nothing, and for most questions they are the answer, so the expensive half waits until you ask for it.
- My file will not upload somewhere. What should I look at?
- The codec line first. A file can be called .mp4 and hold video that a site refuses, and H.264 with AAC is what almost everything accepts. After that, the resolution and the bitrate, which are what upload limits are usually about.
- Why does it say the length is not stated?
- Some files genuinely do not record one, particularly recordings that were interrupted or streams saved directly to disk. The file usually still plays; players work the length out as they go.
- Is the file uploaded in order to read it?
- No. Reading a file here is exactly like converting one: it happens in your browser, and nothing is sent anywhere.
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