Video Analyzer
Check a video file for duration, resolution, codec, frame rate, bitrate and audio details, with preview frames. Everything stays on your device.
What this analyzer shows
Choose a video and it reports the duration, resolution, aspect ratio, file size and average bitrate. For MP4, M4V and MOV files it also reads the file's own index to find the video codec, frame rate, number of frames, whether the picture is HDR, and the audio codec, sample rate and channels. It then grabs a few preview frames spread through the clip.
Reading the results
| Item | What it tells you |
|---|---|
| Resolution | Width and height in pixels. 1280×720 is HD, 1920×1080 is Full HD and 3840×2160 is 4K. |
| Video codec | How the picture is compressed. H.264 plays almost everywhere, HEVC (H.265) is smaller but not supported by every browser, and AV1 and VP9 are common on the web. |
| Frame rate | Frames per second. 24 is cinematic, 25 and 30 are typical for video, and 50 or 60 look smoother for fast action. |
| Overall bitrate | File size divided by duration, covering video, audio and container overhead. Higher means more data per second, and usually higher quality. |
| Playback in this browser | Whether your browser can decode each common codec. A file that will not preview may still play in a desktop player. |
Why some details are missing
Browsers only tell a web page the size and length of a video, not its codec or frame rate. This tool therefore reads the file structure itself, which works for the MP4 and MOV family. For WebM, MKV, AVI and others you get the browser-reported values only, and files your browser cannot decode may not open at all. Files are processed on your device and never uploaded, and large files are fine because only the file index is read, not the whole video.
To shrink a video frame into a smaller picture, try the Image Compressor, and for checking audio levels in the soundtrack use the Audio Analyser.
Frequently asked
Is my video uploaded anywhere?
No. The file is read by your browser on your own device. Nothing is sent to Curious Assistant or to any other server.
Why does it not show the codec for my file?
Codec and frame rate are read from the MP4 or MOV file index. Other containers such as WebM, MKV and AVI only show the values the browser reports, which are duration and resolution.
Which video formats can it open?
Anything your browser can play, usually MP4 with H.264, WebM and Ogg. MOV works in Safari and often in Chrome. Files your browser cannot decode will show an error, although MP4 and MOV details can sometimes still be read from the index.
Is the bitrate shown the video bitrate?
It is the overall average, the file size divided by the duration. That includes audio and container overhead, so the video stream alone is a little lower.
Can it handle very large files?
Yes for MP4 and MOV, because only the index near the start or end of the file is read. Preview frames need the browser to be able to play the file, which can be slow for very high resolution footage.
Why is the frame rate not a whole number?
Broadcast standards use rates such as 23.976, 29.97 and 59.94 fps. They are slightly under 24, 30 and 60 and are completely normal.