Wanikani teaches about 6000 words, so I wouldn’t say it’s only for kanji. But it’s true that these are all written with kanji (it does have some that aren’t usually written with kanji too). Somewhere in the middle it’s probably a good idea to do something about katakana words, onomatopoeia, and a lot of other words that are commonly written in kana. And of course grammar.
Indeed, it only teaches kanji but it’s invaluable to me.
Before wanikani I studied japanese for about a year and I got very mad because I had as much trouble remembering new vocab after a year of study than in the very beginning.
In my mind, the more I would learn, the easier it should get, but it didn’t.
When i tried out wanikani everything became so much better ! Instead of just remembering whole blocks of lines, their reading and their definition, I have a much keener eye and I’m developing a way to make good mnemonics.
Before, for instance, I had so much trouble differentiating 遠い from 速い ! My clue was the little drop on the lower right part of the kanji, and when I found the drop I forgot if the one with the drop was far or fast ? Ghaaaaa ! Now it’s just so easy the zombie goes far away on his scooter while on my scooter I have to deliver this bundle fast ! (how could I mix up a zombie and a bundle ! what a fool ! ^^)
Before I had to remember this whole package of lines 美術館 was a museum with a reading which was very weird to me. Now i look at it and see ‘beauty-art-public building’, that’s a museum : びじゅつかん.
Plus, when I encounter a new word, I can partially guess its meaning and reading (just as I expected after studying japanese for a year)
Yes, Wanikani doesn’t teach vocab that isn’t kanji, that’s why I add them on my SRS when I encounter them along with the vocab that I encounter which is made from kanji that I already know or kanji which aren’t taught by wanikani.
I still have a long way to go, but I’m very glad that I found this path.
The vocabulary used in Wanikani is there to re-enforce the memory of the kanji, but also to showcase the different pronunciations of the kanji depending on the word it is used in.
You won’t see any vocabulary that is not using kanji, so it is best to have something else on the side for vocabulary specifically, but there is still quite a significant overlap in between.
I’m finding that going through Bunpro is actually helping a little bit with some common kana-only vocab. Other than that, yeah, you obviously just have to learn them in whatever way works best for you as you encounter them, or in some kind of premade flashcard deck.
I’ve got enough SRS on my plate for now with WK and BP though.
Interesting stuff!
Yeh i guess thats sort of my point, learning kanji and learning vocab are pretty seperate, albeit theres a slight overlap, and amalgamating the 2 together seems to cause people a lot of bother and slows them down.
Im thinking specifically about all the vocab around fruit, veg, marine animals, flowers, etc, that have complicated kanji but are very commonly written in kana. If youre learning vocab through kanji, youre going to spend much longer and have a much harder time establishing a good foundational understanding if you are trying to learn words like lemon (檸檬) or rose (薔薇) in kanji rather than kana.
However it definitely seems to be used alongside other systems for vocab which is great.
I didnt touch kanji for the first year of study, but I guess i had a slightly antiquated method of studying 
You do learn vocab that is usually seen written in kana, in WaniKani. In fact a bunch of them are also grammar points in BunPro. I quite like that you get to see the versions that have a kanji character in them, just in case you encounter them written that way in the wild.
I definitely didn’t expect when I started trying to learn Japanese ~a year ago that I’d be frustrated that not enough words were written using kanji sometimes, but that is definitely where WK put me. 
Hahah vast swathes of hiragana are indeed horrific!
Same lol
And ふりがな is the another Devil!
If I had to say, I would say for me the meat of the grammar is in N3/half of N2 (the other half can piss off back to the boardroom/middle ages). It all depends on what your goals are. As I always feel that I cannot quite be specific enough in Japanese, the N3 and N2 levels and their variants of earlier grammar felt to be exactly where the “meat” is.
N5/N4 is the easiest by far (with a few exceptions) exactly because at that point you are skipping along oblivious to the fact the you going to be replacing 25% of all things with something else 66% of the time.
A means B. La la la. Nuance crit 3 months later.
I dunno… you make it sound like N3/N2 are the spices to me.

I was, and still am to some degree, really far behind in terms of grammar. At the time I already knew about 20% of N3 vocabulary and 80% of N3 kanji (writing), I only knew about half of the N5 grammar, which is, admittedly, quite embarrassing. I quickly jumped onto Bunpro less than 2 months ago because I don’t really like reading. In the beginning, I couldn’t really understand 80% of sentences in NHK News Easy or practically any sentence in the seinen manga I’d be interested in. Today I’ve learned the last N4 grammar point, while not making a whole lot of vocabulary progress, and I can tell you that I’m now able to get the gist of the majority of conversational, non-technical sentences In the simpler kind of seinen manga and upon reading an entire NHK News Easy article, I have a very general idea of its content. I can’t really interpret the grammar very well in a spoken form because it’s still far too fast for me, but that is more of a matter of practice. What I’m trying to say is that yes, the N5 and N4 grammar is indeed very important and as has been said before, it’s another natural case of Zipf’s law. Lastly, a worthwhile consideration is that Bunpro alone is a poor grammar teacher because you only reinforce specific example sentences and phrases in your memory, so what you really need to make any use of it is to practice those grammar points elsewhere to actually get a hang of how they’re used. That being said, of course, the more advanced grammar is still very much necessary, and at the very least the N3 and N2 grammar is relatively commonly found even in daily conversations, but given the N4 knowledge, you can approximately deduce many of the more advanced rules. After all, that’s how humans naturally learn languages.
Addendum: I used to use Duolingo (the older version) daily for about 3-4 years and I haven’t learned virtually anything compared to the 8 months of WaniKani, 7 months of KameSame and 2 months of Bunpro, so if anyone is still honestly using that to learn anything but the very basics of western languages, you’re almost certainly just wasting your time there. Granted, the new version of a bit better, largely thanks to the introduction of kanji instead of using virtually exclusively kana (for those who haven’t experienced it, it was an immeasurable pain to deal with the machine-translated sentences written in kana only and that’s why kanji is absolutely essential to comfortable reading), but it still doesn’t even begin to compare to less guided, more hardcore learning methods that don’t give you any immediate gains, but eventually teach you far more than Duolingo could ever hope to.
I hear what you are saying about it being the spice as it “adds flavour to the base material”, but fundamentally it depends on how you define “meat” and what your goals are:
Cambridge defines the “meat” of something as: important, valuable, or interesting information.
If you are interested in something more nuanced than genki I robot sentences, N3+ is definitely where the meat is at.
Others, with a focus solely on attaining basic conversational ability are going to find the “meat” in N5/N4.
I have limited experience with N1 things, so I cannot comment on if it just falls off beyond N2, but so far, N2 has provided me with more valuable and interesting information pertaining to Japanese in terms of my goals. So I stand by my “meat”. XD
Are there unnatural cases?
Also welcome to the forums!
…And there we go, I’m at this point again almost a year later. 
Not super long after this point last year, work got really busy, and I was still blasting through WaniKani, so I put BunPro on vacation mode and unfortunately it stayed that way for almost the rest of the year. In the meantime, I reached level 60 of WaniKani, though months later it’s only quite recently that it’s been feeling like my review load is lighter.
Anyway, in November I reset every grammar point here, and this time around I’ve been doing a steady 3 grammar points per day, instead of the 6 or more I was often doing the first time around. This is much better! I am also loving the improvements that are being added in real time right now.
Anyway, glad to be “fluent” in N5/N4 again. 
I’ve found that three new grammar points per day is my sweet spot, too. I blasted through N5 and N4, though because I found most of that was review for me (I came into Bunpro having already studied Japanese for 18 months before).
That being said, in response to your original post, I’d say that N3 contains a good amount of very common grammar. Based on what I’ve seen so far, while N3 does have some things usually only used in formal speech or writing, N2 is really where things start to fall off (in terms of things not commonly used in everyday langauge). I’m almost done with N2, and I’ve noticed several things that I had never encountered before. That being said, I’ve only been studying for two years, so my experience is limited. I think @hunglikeconan came to the same conclusion.
While I do use Duolingo still (entirely for practice and exposure to new vocabulary), I completely agree with your assessment. In fact, I’ll go further: for Japanese, Duo is a garbage learning product. Absolute garbage.
(If you use Duo and you like it, fine. I use Duo and I hate it–and for good reasons.)
so far I have done 45 points in N3 (doing 2 a day) and I am enjoying them a lot, way more than N4.
As soon as I finish it and start N2 (then I will do only 1 point per day) I will try reading manga and watching anime with japanese subtitle somehow (somehere?) to fix those points in my mind.
I am not into books or novels, even in my native language and english I dont like to read all that much 
I went into Duolingo Japanese the other day for a few minutes, because I hadn’t looked at it in maybe a year or more. It seems there have been some improvements, like some of the audio seems to be real human voices, and there are listening-practice dialogues and such. But I don’t doubt that, overall, it’s still not a great tool for learning Japanese. It’s what I started with (2 years ago) and I abandoned it within weeks.