Tubern is a Youtube converting service written in php with youtube-dl as backend.
The name Tubern comes from tunfisk on tube.

Just because a certain bro said he liked tunfisk on tube one day.
He then went on to say Tubern during the making of Tubern. So tubern was born!

Tubern supports youtube playlists, channel and single video links. it will extract the audio so you get a mp3 file with the right tags.
The Nightcore, Nightcore Japan and Regular is for getting the tags right. This might be automatic in the future. Regular is Default tagging.
Nightcore is tagging for nightcore songs
Nightcore Japan is tagging for Japanese Nightcore songs.