Originally Posted by Orochimaru
How much kanji do I need to know to read a light novel? ...How many/which kanji?
Since light novels are popular fiction mainly aimed at teenagers, if we look at the matter from this angle, probably you need know Kyōiku kanji
(approx. 1000) and kanji which Japanese students learn at junior high schools (approx. 1000).
If the light novel you read has furigana
, they will help you to read the text to some extent, though.
These links may be useful to you.
Kanji which Japanese students learnt at junior high schools (a somewhat old list):