日本語を学ぶ
A free, self-contained Japanese learning platform. Practice kana, kanji, vocabulary, and verb conjugation—all in one beautifully designed toolkit.
Katsuyō Academy is a passion project built by a learner, for learners. It's not trying to replace a textbook or be the next language learning app. Instead, it's a focused set of interconnected tools that cover the foundational building blocks of Japanese—the things you'll reference and practice over and over again.
Everything runs locally in your browser. No accounts, no tracking, no servers. Just open it and learn.
"A free, offline-capable Japanese study suite built by a learner for learners—covering kana, kanji, vocabulary, and verb conjugation in one cohesive, beautifully designed package."
Six interconnected tools covering the foundations of Japanese
Practice all 104 hiragana and katakana characters. Learn both Japanese writing systems side-by-side with audio pronunciation, clear charts for basic kana, dakuten (voiced sounds), and combination characters. Click any character to hear how it sounds.
Clear, visual explanations of how Japanese verb conjugation actually works. Understand the why behind the patterns, not just the rules. Learn to identify verb types, understand the hiragana sound system, and see step-by-step walkthroughs of each conjugation type.
Comprehensive quick-reference conjugation charts covering 16 verb forms for all three verb types: Godan (五段), Ichidan (一段), and Suru (する). From basic forms (negative, polite, past) to advanced (passive, causative, conditional), color-coded tables show you exactly how each form is created. Perfect for quick lookups or comparing patterns side-by-side.
Browse all 129 verbs in our database, organized by type (Godan, Ichidan, Suru) with kanji, hiragana, and English meanings. Search to find specific verbs instantly, or filter by JLPT level (N5, N4, N3) to focus on vocabulary appropriate for your level.
The heart of Katsuyō Academy. Practice conjugating verbs across 16 different forms with instant feedback. Choose Random modes by difficulty (Basic/Intermediate/Advanced) or focus on specific forms. Filter by JLPT level to match your study goals. Get detailed hints showing exact rules and examples, plus error explanations when you make mistakes. Skip questions without penalty when stuck. Your progress saves automatically, and the Practice Report shows your statistics and weak areas.
Practice Japanese dates, weekdays, months, and numbers. Questions cover today's date, future/past calculations, relative days (きのう, あした), and large numbers. Full sentence answers required — build proper grammar habits with です and でした endings. Includes a handy reference chart for the tricky readings.
Practice 496 essential Japanese words with intelligent flashcards. Study with hiragana, kanji, and katakana across 8 different learning modes. Toggle between Japanese→English or English→Japanese practice, show/hide kanji and katakana readings, and see both scripts side-by-side. Smart shuffle prioritizes unseen cards, progress tracking shows cards studied, and the beautiful vintage design makes learning engaging.
Practice 2,300 kanji from the acclaimed Kodansha Learner's Course. Each card shows the kanji character, English keyword, on'yomi and kun'yomi readings, plus example vocabulary with meanings. Filter by level (Beginner, Intermediate, Advanced), shuffle cards, or jump to any KLC number. Keyboard shortcuts included!
One HTML file. No installation, no accounts, no internet required after loading. Save it locally and study anywhere—on a plane, in a café, wherever you learn best.
Not a gamified app or a full curriculum. Just focused, interconnected reference and practice tools for the foundational building blocks you'll use every day.
The Learn section explains why patterns work the way they do. When you understand the logic, conjugation becomes intuitive instead of a memory test.
The Conjugator doesn't just say "wrong"—it shows the exact rule you needed and identifies your specific error. Flashcards track your progress and prioritize unseen cards.
Warm, aged-paper aesthetics with clean typography. It feels more like a well-crafted study journal than a typical language app. No ads, no clutter, no distractions.
A passion project born from my own struggles learning Japanese. No paywalls, no premium tiers, no "sign up to continue." Just free resources for anyone who wants to learn.
Whether you're learning kana, mastering kanji, studying verbs, building vocabulary, or practicing dates—choose your path below.
A note from the creator:
I built Katsuyō Academy because I needed it myself. Scattered textbook chapters, confusing online resources,
flashcard apps that didn't quite work the way I wanted—I wanted everything in one place, designed the way I learn best.
This is that place. If it helps you too, then it's done its job. 頑張ってください！