I find that the guides from WK are kind of vague, some places it seems to suggest that you should start after you’ve hit level 10, and others it says after 20.
What does the community think? Should I wait till I hit level 20 WK to begin with grammar, or should I just begin now?
Learn grammar as soon as you can. No point in waiting until you know an arbitrary number of Kanjis, I can’t see how that would help you.
Start now, there’s no point in waiting since most resources will come with furigana and/or romaji to help you out.
This is question is asked often, you can find quite a lot answers even in this minimal search.
https://community.wanikani.com/search?q=start%20grammar
I would argue it should be started even before WK but some how this place seems be the first stop for many people. Tofugu must get a lot of traffic.
From my perspective, after taking the five month class, you could take grammar lessons directly even if you just started kana and kanji study.
Begin as soon as possible and you have time for it.
I started at level 0 (before finding Wanikani) but slowed down as I realized that learning the Kanji and Vocabulary was incredible helpful for all of the grammar exercises.
Summary: I would just focus on WK for the first 15-20 levels. Most people will reply “as soon as possible, if you have the time”. Well, TIME is a big variable and a huge blocker for a lot of people. That´s probably why this question is being asked in the first place.
Personal context:
I am much much more adept at grammar now. I can actually understand the Kanji samples in Tae Kim and Bunpro, while it was extremely hard at level 0.
I plan to reach lvl 20 (currently lvl 11) before increasing the grammar focus again (I’m around N4 according to Bunpro)
Depends on your resource, but I think you should start ASAP personally. If you’re using a textbook like Genki, then all kanji will have furigana in it so there’s no point in waiting. The only exception I can think of is if you’re using Tae Kim, you may want to wait for level 10 since he doesn’t include furigana, but there will still be plenty of kanji his guide uses that you don’t know at level 10, so you’ll still have to look stuff up. Since it’s an online guide, however, it won’t be hard to look up kanji.
Just to clarify, I’m not looking to learn a set amount of kanji before studying grammar, I mostly want a broader vocabulary. Last time I tried to learn grammar I was frustrated that when I learned new grammar, I barely had any words to produce sentences with. It was like trying to build a house with only a hammer and nails, but no wood, and instead of getting wood I just acquired more construction tools.
In other words, it’s not about how I’m worried I won’t know enough kanji to understand grammar resources. It’s that I can’t motivate myself to learn grammar if I can’t use it to make my own sentences.
So the question, really, is at what point in WK do you think I know a large enough amount of words to start making useful conversational sentences once I learn grammar?
Again, as soon as possible is not a valid answer, because I tried that, several times over a few years before I ever found WK, and it doesn’t work for me. It feels pointless and I lose all motivation when I don’t have a decent vocabulary.
My approach for both Japanese and now also French has been to wait until I get frustrated because I don’t know enough grammar and then study grammar…
Contrary to a lot of people it seems, I find grammar a lot easier to pick up when I:
Horses for courses and all that, basically…
Short answer When you Feel ready.
But if you find yourself loosing motivation, then move your focus from learning Kanji to learning Vocabulary.
get the core 10000 deck from anki or kitsun, and just go over the vocabulary, just paying attention to the readings(as in sounds) and the meaning, learn the words first, then you can use those words to build your sentences. You can go back and learn the kanji later. Use hiragana, or romanji if necessary, just as a place holder for the word or thought. as you learn more kanji, you can replace them
I am not saying this will work. I am just offering a suggestion. I personally am just learning a little bit at a time, slowly building my kanji and vocabulary, and trying to piece-mail grammar through sheer force of will, may not actually work, but we’ll see.
Much like the other replies on here, I started learning vocabulary early on, even before I thought to learn Kanji. I’m taking an intermediate university Japanese course right now (using Genki I & II), but I didn’t start WaniKani until this summer.
Highly recommend beginning as soon as you can
Mi customized recommendation for your would be to keep focusing on WK until you have a bit more vocabulary and can recognize more Kanji. This will allow you to form more sentences once you actually learn the grammar stuff. For example: I was focusing in learning the vocabulary AND the grammar structure AND the kanji while starting grammar, and it was incredible painful and hard to grasp.
WK taught me the Kanji, a lot of basic vocabulary and how to read things, so now grammar just “makes sense”: I can plug and play the words alongside the grammar structure like a Lego.
We are both lvl 11, I would say keep pushing till lvl 20 and then work in parallel with Tae Kim or Human Japanese.
PD: I also found out that when learning vocabulary, things never really “stuck” until I learned to read them in WK. Example: 台所 - Kitchen: daidokoro = machine DAI + DOKORO (rendaku from tokoro) = place. I had seen the word months before but until I saw WHY the word was composed and sounded like that, it stuck with my brain.
Immediately. WK does a pretty bad job explaining vocabulary if you haven’t learned grammar yet. I struggled so much my first time (reset at level 13) so I stopped and concentrated more on grammar instead of vocabulary. Came back and so much stuff made sense. I don’t feel as lost as I did before.
You learn vocabulary by studying and getting more into the language. It’s a waste of time to sit there reading a vocabulary list just for the sake of being able to write some basic sentences with the grammar and kanji you learn initially. This is a long haul.
So yeah, I agree that you should learn grammar ASAP and do it alongside WK, that way you’ll be able to start reading soon, and with that, you’ll learn vocabulary.
Only then will you really be able to write stuff in japanese
From the point of view of someone who has purchased way too many books, avoid romaji at all costs.
Thanks, I really like this advice! I think this approach will work for me. As of right now, I think maybe I wish I knew more grammar, so I’ll go learn grammar until I feel less frustrated. Then rinse and repeat until I hit level 20. Then I will start trying to read simple material to put it all into context and start working on my actual comprehension of the language.
Nice simile! Most textbooks will give you a number of words to learn per chapter to practice with though
After reaching level 15, I started Minna no Nihongo book vol 1 and I didn’t even had to buy the translation book as I understood nearly everything with all the vocabulary and kanji from Wanikani.
Although my teacher was a bit surprised that I knew complicated words, made of several kanji, but didn’t know simple vocabulary like “window” or “wall”. 
That is funny! But it also goes to show that WK doesn’t necessarily teach the most useful vocab for early grammar study. You could find a genki or minna no nihongo chapter by chapter word deck on Memrise or Anki and study those. (I get the feeling you are using online resources for grammar? That maybe don’t have built-in wordlists?)