A common way to tell if a manga is seinen is by looking at whether or not furigana is used over the original kanji text: if there are furigana on all kanji, the title is generally aimed at a younger audience. The title of the magazine it was published in is also an important indicator. Usually Japanese manga magazines with the word young in the title (Young Jump for instance) are seinen. Other popular seinen manga magazines include Ultra Jump, Afternoon, and Big Comic.
List of seinen manga
Please see the category Seinen for a list of manga that are considered "seinen".
