Methodology

Why this order

Every word, kanji and grammar pattern here sits on one shelf, sequenced N5 → N1. The order is not a secret formula — here is exactly what decides it, with sources and real numbers.

What decides the order

1. 1Vocabulary: public JLPT lists, then per-word sourcesThe JLPT stopped publishing official vocabulary lists in 2010, so level tags follow the last published specification and widely used reference lists, cross-checked against at least two sources. Words outside those lists carry their own source note — 259 words so far: 35 matched to a JLPT-era list, 180 estimated from dictionary and frequency data and labeled as estimates, 44 placed deliberately for a topic or scene.
2. 2Kanji: JLPT lists, the Jōyō table, and frequency1295 characters follow the published JLPT-era lists. The rest are shelved by an explicit basis: 93 from the official Jōyō table (2010 Cabinet revision), 57 by newspaper frequency within the Jōyō set, and 13 place-name kanji you meet on signs and tickets.
3. 3Grammar: triangulated lists, grouped by functionEach level's pattern list is fixed only after cross-checking several published grammar references and standard textbooks. Inside a level, patterns are arranged into 14 function groups and sequenced so each step leans on the one before it.
4. 4Same pool, different shelvesLevels are the main road, but the same pool can be walked in other orders: 7 textbook paths (99 chapters, mapped from the publishers' official syllabi) and a frequency view ranked by the JMdict priority corpus (5702 words). A different shelf never forks the content — it only re-sorts it.
5. 5The shelf decides what's next — memory decides whenStudy order and review timing are separate systems. Shelves sequence new material; the spaced-repetition scheduler brings each item back based on how well you remember it, not on where it sits.