We’ve always advocated learning Japanese with anime here at KawaJapa. It can be done and it should be done!
However, to actually learn anything you need subtitles. Japanese subtitles. English subtitles won’t help you learn Japanese with anime, and just listening to things you don’t understand or barely understand won’t do much good either.
Back when I started, and when I started writing about it, getting quantities of Japanese-subtitled anime was a somewhat complicated business. Usually you had to find the anime and the subtitles in two different places and tie them together by hand – often re-timing them several times.
Fortunately for you (you young folks have it so easy these days) there are simpler ways to do it now.
Stop press: there is now a new Japanese subtitled anime site called AnimeJpnSub. The layout is very bare-bones and I don’t think it has anything the others don’t. However, it is completely ad-free, which is a plus, and seems to work seamlessly.
Both sites have both Japanese and English subtitles and allow you to turn them on and off at will. I strongly advise not watching with English subtitles because the human brain is hardwired to take the line of least resistance and you won’t learn much even if you think you will.
However, English subtitles can be useful for when you aren’t sure what a particular expression or way of speaking in Japanese means. If you use them for this, it is better to do a quick check by switching a single subtitle to English while paused and then switching back to Japanese before restarting. Think of it as a quick look-up tool rather than a functioning subtitle.
There is a lot of good anime between the two sites, including all of Ghibli on Anime Japanese Subtitles and the delightful Shirokuma Cafe on Animelon. Not to mention all the regular shounen stuff that I tend not to bother with.
I used not to be a fan of streaming anime, but these two sites have changed my habits radically. Recently I’ve been enjoying Flying Witch, Hotarubi no Mori e and Hoshi wo Ou Kodomo. Being a doll I tend to like gentler anime with fantasy themes, but whatever your taste you’ll find things you like on these sites.
If you are starting to learn Japanese with anime, life just got a whole lot easier!