Answer #2

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Here’s a quick primer on YouTube resolutions. Skip this paragraph if you already understand it and just want to know the audio bitrates. On many videos, YouTube allows users to select from different resolutions. These are 240p, 360p, 480p, 720p, and 1080p. Without going into too much detail, this number refers to the vertical resolution of the source video in pixels, and generally the larger the number the more crisp the video. Not all videos have all these options, and many only give 240p or 360p. This is because for YouTube to offer higher resolutions, the originally-uploaded video must meet or exceed those resolutions.

Now on to why this matters for audio quality. YouTube creates multiple different audio files for each upload, and which one is played depends on the video resolution selected. Here are the bitrates I have found for current YouTube videos.
au revoir

Answered By: tagus [186 ]