Inspect YouTube formats without downloading
Paste one public video URL to review format IDs, containers, resolutions, frame rates, video codecs, audio codecs, bitrates and estimated sizes reported for that source.
YouTube Format and Codec Inspector
Review technical media details without downloading the video or exposing direct source stream URLs.
This tool reports what the public source makes available. Private, restricted or removed videos may not work. Direct media stream URLs are never displayed.
Container versus codec
MP4 and WebM are containers. H.264, VP9 and AV1 are video codecs; AAC and Opus are audio codecs. A familiar extension does not identify every codec inside it.
Video-only and audio-only streams
Higher YouTube resolutions are often delivered as separate video and audio streams. A row may therefore show a video codec with no audio codec, or audio with no picture dimensions.
Resolution and frame rate
Resolution describes pixel dimensions while FPS describes frames per second. A 1080p60 stream can require more data than 1080p30, although codec efficiency and source complexity also matter.
Estimated file size
A reported size is a planning estimate when the source does not publish an exact byte count. Variable bitrate, segmented delivery and track merging can change the finished size.
Choose a compatible format
H.264 with AAC in MP4 remains broadly compatible. VP9, AV1 and Opus can be efficient on current software, but older televisions and editors may require conversion.
Privacy and direct stream URLs
The inspector reports technical properties needed to compare formats. It does not display direct media stream URLs or turn private video into public media.
Frequently asked questions
What is a YouTube format ID?
It identifies a particular combination of container, quality and media tracks.
Why does a 4K row have no audio codec?
High-resolution picture and audio are commonly supplied separately and combined for playback.
Is MP4 always H.264?
No. Containers and codecs are different, so inspect the codec rather than relying on the extension.
Are file sizes exact?
Only when the source supplies an exact size; otherwise the value is an estimate.
Does inspection download the video?
No finished media file is delivered; the tool reports available metadata.
Related tools and guides
All video and audio tools · Video download guides · Download troubleshooting · Try the Vyroli Android app