399 Mp4 -

: The standout feature of 399 is its use of the AV1 codec . Compared to older formats like 137 (AVC/H.264), Format 399 can offer similar or even better visual quality at significantly lower bitrates—sometimes reducing file size by 30-50% .

“it visually has the same quality as format 616 (premium) but some videos don't have format 248, so, I don't want to specify a format, just say: "Get the Best Video format available"” Reddit · r/youtubedl · 2 years ago 399 mp4

Users often debate whether to prioritize this format over others when archiving content. : The standout feature of 399 is its use of the AV1 codec

: The standout feature of 399 is its use of the AV1 codec . Compared to older formats like 137 (AVC/H.264), Format 399 can offer similar or even better visual quality at significantly lower bitrates—sometimes reducing file size by 30-50% .

“it visually has the same quality as format 616 (premium) but some videos don't have format 248, so, I don't want to specify a format, just say: "Get the Best Video format available"” Reddit · r/youtubedl · 2 years ago

Users often debate whether to prioritize this format over others when archiving content.

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