youtube-dl https://www.youtube.com/... code example
Example: youtube dl
720p:
youtube-dl -f 22 http://www.youtube.com/watch?v=dQw4w9WgXcQ
360p:
youtube-dl -f 18 http://www.youtube.com/watch?v=dQw4w9WgXcQ
other formats:
https://www.reddit.com/r/youtubedl/comments/aa6uvq/how_do_i_download_a_video_or_playlist_at_480p_only/