Susume Nihongo
進め日本語
Your free AI-powered companion for learning Japanese — master natural phrases, build real confidence, and advance at your own pace.
What is Susume Nihongo?
Susume Nihongo (進め日本語) means "Advance in Japanese" — and that's exactly what this platform helps you achieve.
It's a free, AI-powered Japanese learning web application that provides an integrated toolkit for learners at every level. From AI translations and realtime voice conversation to FSRS flashcards, dedicated quiz pages, a 40-chapter study book, JLPT practice exams, and practical cultural tips — all in one place.
The platform is built with Astro 6, React 19, Tailwind CSS 4, and runs entirely in your browser. A free Google Gemini API key (user-provided) powers the AI features. Everything works offline by default — an account is never required.
Key Features
Everything you need to learn Japanese effectively, all in one place.
Study Book with Ask AI
A structured guide from writing systems to verb conjugation with chapter-by-chapter progress tracking. Ask the AI assistant questions about any chapter and get instant, context-aware explanations.
AI-Powered Lessons
Contextual translations that go beyond literal word-for-word conversion, giving you natural, conversational Japanese.
Grammar Breakdown
Every lesson includes detailed grammar explanations, helping you understand the structure and rules behind Japanese sentences.
FSRS Flashcards
Automatically generate flashcards from your lessons with the same spaced-repetition algorithm used by Anki for optimal retention.
Native Pronunciation
Hear authentic Japanese pronunciation with integrated Gemini TTS technology. Build accurate listening skills from the start.
Kanji & Kana Quizzes
Master JLPT N5 & N4 kanji plus all hiragana and katakana through interactive quizzes with progress tracking.
Multiple Variations
Learn different ways to express the same idea — from casual to formal registers — and understand the nuances of each.
Login & Cloud Sync
Optionally sign in with Google to sync your settings, flashcards, quiz progress, and history across devices. Everything works offline by default — an account is never required.
Live Sensei — Voice Practice
Realtime voice conversation using the Gemini Live API with configurable voices (Zephyr/Kore) and thinking levels. Practice speaking Japanese naturally with bidirectional audio streaming.
JLPT Practice Exams
Full N5 and N4 timed exams with vocabulary, grammar, reading, and listening sections. Track your per-section stats and build exam confidence.
Google Gemini API Key Required
To use Susume Nihongo, you need a free API key from Google AI Studio. Copy your key and enter it in the app settings to enable translations and text-to-speech. It's free, takes under a minute, and no credit card is required.
Important Information
AI Accuracy Note
AI models may make mistakes, and translations may not always be perfect. Translations aren't literal and may vary, as the algorithm reflects cultural aspects of Japanese. Responses are polite and friendly — you'll want to understand how they differ from formal Japanese. Please review results carefully and use your judgment.
API Limits
You're using a free Google Gemini API key, so there may be limits on how much and how often you can use it. Check your usage in Google AI Studio.
Free, No Ads, No Tracking
All content on Susume Nihongo is completely free. There are no advertisements, no analytics trackers, and no third-party tracking scripts. Your data stays in your browser by default. An optional Cloud Sync Pro subscription ($5/month via Stripe) is available for cross-device sync — but every feature works fully without it.
Ready to Start Learning?
今すぐ勉強始めよう — Start studying right now. It's free, runs in your browser, and takes only a minute to set up.
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