Japanese study guide
Cotobara vs Bunpro: Grammar vs Vocabulary, and Why Both
Bunpro is spaced repetition for Japanese grammar; Cotobara is a finished 8,700-word vocabulary course. Where they differ, and how they fit together.
Bunpro and Cotobara sit on different halves of the language. Bunpro is a spaced-repetition system built around Japanese grammar: roughly 900 grammar points from N5 to N1, drilled as fill-in-the-blank sentences. Cotobara is a spaced-repetition system for vocabulary: a finished course of more than 8,700 words and expressions, N5 to N1, every one already chosen, ordered, explained and voiced. If you can read a sentence and follow its structure but still don't know what it is about, that is a vocabulary gap, and Cotobara is what fixes it.
What Bunpro covers
Bunpro drills the JLPT grammar syllabus — particles, conjugations and set patterns — with cloze-style SRS, and ships JLPT practice tests alongside it. Grammar is the center of the product, and は vs が or てある vs ている is the kind of thing it is shaped around.
It also sells vocabulary decks: context sentences and themed sets drawn from anime, manga and textbooks, included with a subscription. So the two products do overlap on vocabulary, and the useful question is not which one has words in it, but who decided the order you meet them in.
Decks you assemble vs a course that is finished
Bunpro's vocabulary is organized as decks you choose — a JLPT level, a textbook, a series. Picking the decks, and deciding what order to run them in, is left to you.
Cotobara makes the opposite choice. There are no decks to pick, because the ordering is the product:
- More than 8,700 words and expressions, N5 to N1, ordered by JLPT level and by how common the word is — not alphabetically, and not by the order someone happened to add them.
- Every word arrives as a written lesson, not a bare front-and-back card: what it means, how it is used, and — where a word is easily mistaken for another — what separates them.
- Recall, not recognition. Reviews ask you to produce the word, which is the skill that fails people in a reading passage.
- More than 17,000 words and example sentences are voiced, in a male and a female voice, so every entry has audio rather than the subset a studio budget would cover.
- WaniKani import, so kanji you have already burned never clog your queue.
Grammar and vocabulary are not substitutes
You cannot grammar your way out of not knowing words, and you cannot vocabulary your way out of not knowing grammar. A JLPT reading passage needs both at once:
- Grammar is the skeleton: how the words connect.
- Vocabulary is the flesh: what the sentence is actually about.
The two failure modes feel completely different in the exam hall, which is why a grammar tool and a vocabulary tool are not competing for the same slot in your routine.
How they fit together
A clean daily routine looks like:
- A grammar source — Bunpro, or your textbook — for the point you are on.
- Cotobara for the vocabulary of your JLPT level, with example sentences that let you see that grammar in the wild.
- A kanji tool like WaniKani if you still need reading practice; Cotobara imports it so nothing overlaps. See How to use Cotobara with WaniKani.
The bottom line
Cotobara does not teach grammar, and does not pretend to. What it does is the vocabulary half, completely: 8,700+ words as a finished course rather than decks to assemble inside a grammar app, with a free 30-day Premium trial to see whether that is the half that has been failing you. For why recall matters so much on the vocabulary side, see Why you can recognize kanji but can't recall words.