Can I travel to Japan alone at 19?

Hey everyone,

I’m 19 years old and planning a solo trip to Japan soon. Since the age of majority in Japan used to be 20 (and some things like alcohol/drinking age are 20), I just want to be sure about the travel requirements:

Do I need any kind of parental consent, a travel letter, or a copy of my birth certificate to board my flight or enter Japan as a tourist at age 19 alone?

I’m from Denmark btw