video tool
Video metadata viewer
Open an MP4, MOV or WebM and this video metadata viewer reads its duration, width and height, aspect ratio, frame rate, file size, overall bitrate and whether there is an audio track, plus the codec of every track. The figures come from the file's own header and from the browser's decoder, so a clip the browser cannot play still reports what its header says.
Loading the tool…
- Runs on your device, nothing is uploaded
- Free, no sign in
- No watermark, no file limit
How it works
- 1
Open the video
Choose a file or drop it on the panel. Only the header and the first moments of the clip are read, so even a large file opens in a moment.
- 2
Read the summary cards
Duration, resolution, aspect ratio, frame rate, file size, bitrate, audio and container sit in a grid of cards, each in plain words.
- 3
Check the tracks and notes
The table lists each video, audio and text track with its codec and details. Notes below flag a clip the browser cannot play, a sideways recording or a missing audio track.
- 4
Copy the details
Copy the details puts every figure on the clipboard as plain text, ready for a support ticket, a brief or a spreadsheet.
Two readings of one file
A video file has two layers: the container, which holds the tracks and an index of where each frame sits, and the encoded streams inside it. The container header can be read byte by byte without decoding anything, which is how this tool finds the codec names, track sizes, sample rates and the frame count of an MP4, MOV or WebM. Separately, the browser's own media engine opens the file the way a player would and reports the size it will actually display and the true length. When both readings are available the browser's display size wins, because it already accounts for rotation; when the browser cannot decode the picture, the header still answers.
Frame rate and bitrate, and what they tell you
In an MP4 or MOV the frame rate is the number of video samples divided by the track's length, so 1,800 frames over 60 seconds reads as 30. WebM files often store a default frame duration instead, and recordings made by a browser store neither, in which case the tool plays a second of the clip silently and times the frames. Overall bitrate is simply file size in bits divided by duration; it tells you how heavily the clip is compressed. Screen recordings and phone clips vary a lot here, and a high figure explains a large file better than resolution alone. MP4 headers also give a per track bitrate, shown in the table.
Checking a clip before it goes into a video
The usual reason to look is an upload that failed or a clip that looks wrong. A clip scene in the OneCraft video builder takes MP4, WebM or MOV up to 200 MB, and the notes say whether the file fits. Phones often record portrait video as landscape pixels with a flag to turn it, which the tool reports as recorded sideways. A silent clip shows no audio track, which matters when you plan to keep the clip's own sound. And a frame rate far from 30 or 25 is worth knowing before mixing clips in one edit.
Limits worth knowing
Browsers decode a fixed set of codecs. H.264 in MP4 and VP8 or VP9 in WebM play everywhere; HEVC depends on the system, and ProRes, DNxHD and most AVI files never play in a page. For those, the summary comes from the header alone, there is no measured frame rate, and a note says so. Files in other containers that the browser also cannot open show only their size and type. Creation dates are shown when the header carries one, and many editors write none. Nothing is uploaded and nothing is stored, ever.
Limits
- Codecs the browser cannot decode show size, container and what the header holds, but no measured frame rate and no playback.
- A file that is neither MP4, MOV nor Matroska and that the browser cannot play shows its size and type only.
- Frame rate comes from the header when it is there; otherwise it is measured over about a second of playback and snapped to the nearest common rate, so a variable frame rate clip shows an average.
- The video header must sit in the first 64 MB of a moov box, which covers ordinary files; very long MP4 recordings with huge sample tables are read by the browser alone.
What it does not do
- It does not edit or strip metadata.
- It does not read camera EXIF style tags such as GPS location or lens.
- It does not convert, trim or compress the video.
Questions people ask
How can I tell if a video is 4K?
Look at the resolution card. Ultra HD 4K is 3840 by 2160 pixels, and cinema 4K is 4096 wide. A portrait phone clip reads 2160 by 3840. If the card shows 1920 by 1080, the file is full HD, whatever its name says; the pixel size in the file is the only reliable test.
Why does my phone video show as recorded sideways?
Phones often store the picture in the sensor's landscape orientation and add a flag telling players to turn it. The header reports the stored size and the turn, while the resolution card shows the upright size a player displays. Editors that ignore the flag show the clip on its side; re-exporting it bakes the rotation into the pixels.
Why is the frame rate 29.97 and not 30?
29.97 is the rate inherited from American colour television, 30000 frames every 1001 seconds, and many cameras and phones still record at it. The difference from 30 is one frame in about 33 seconds, invisible in viewing but relevant when syncing audio or subtitles across long clips. The tool shows the exact figure.
What does a high bitrate mean for my file?
More data per second, which usually means less compression and a larger file for the same length. Phone video often runs 10 to 20 Mbps at 1080p, while a clip prepared for the web runs nearer 5. A high figure is not a problem in itself; it explains why the file is big and why an upload is slow.
Does reading the file change it in any way?
No. The file is only read, never written, and nothing is sent anywhere. The browser opens it from your disk into this page, reads the header and a moment of playback, and forgets it when you close the tab. Your original keeps its exact bytes, dates and name.
Put the clip into a video
Take what you made here into videos.
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Background reading: the question page on this.
Written and checked by the OneCraft team. Last checked .