Immerse Japanese — Learn Japanese While Browsing

Learn Japanese without changing your browsing habits.

Immerse Japanese replaces English nouns with Japanese as you read any webpage. In Peek mode (on by default), words stay readable in English but are highlighted — hover to reveal the Japanese. No disruption, no dedicated study time, just passive vocabulary exposure every time you browse.

── HOW IT WORKS ──

• Immerse Japanese scans page text and replaces English nouns with their Japanese equivalents
• Replaced words are highlighted
• Hover any highlighted word to see kanji, kana, romaji, and the English meaning
• Click "See examples on Tatoeba →" to browse real sentences using the word
• Save words you want to remember — review them later with built-in spaced repetition (SRS)

── FREE FEATURES ──

• N5 vocabulary (600+ core words, JLPT beginner level / A1)
• All display layers: romaji, kana (hiragana/katakana), kanji
• Peek mode — highlight words, hover to peek at Japanese
• Word saving + spaced repetition flashcard review
• Control replacement density (10–100% of eligible words)
• Articles-only mode (body text only, skip nav/headers)
• Site exclusion list
• Dark mode

── PREMIUM — $29, one-time, no subscription ──

• 10,000+ words across N4, N3, N2, N1, and news/current-affairs vocabulary — 16× more than the free tier
• YouTube caption replacement — learn while watching ⚠️ experimental feature, may break on YouTube updates
• Anki CSV export — import your saved words into Anki

Your vocabulary data is stored locally and exportable as JSON at any time. If development ever stops, the extension keeps working.

── ACCURACY NOTE ──

Immerse Japanese does mechanical noun replacement — it doesn't use AI translation. This means it's fast, private, and works without sending your browsing data anywhere, but the replacement may occasionally feel out of context. This is by design: the goal is vocabulary exposure, not perfect translation. Peek mode keeps English readable so this is never disruptive.

── PRIVACY ──

All word replacement happens locally in your browser. No browsing data is ever sent to any server. Premium license validation contacts our server only to verify your license key — no page content or browsing history is included. No tracking, no analytics.

── NO ACCOUNT. NO SUBSCRIPTION. NO STUDY TIME. ──

Immerse Japanese runs entirely in your browser. No account required. No subscription. No background service. Japanese vocabulary only — because that's the one thing you actually want.

No dedicated study time needed. Vocabulary exposure happens automatically while you read the things you already read. Works alongside Anki, any other study method — or entirely on its own.

── FAQ ──

Q: Why only nouns?
A: Verbs and adjectives inflect differently in Japanese, making mechanical replacement prone to grammatical errors. Nouns are safe to swap directly.

Q: Does it work on all websites?
A: It works on most websites. Pages that use strict Content Security Policies (like some enterprise tools) may limit what extensions can do.

Q: Can I control how many words get replaced?
A: Yes — use the "Replace" slider (10–100%) in the popup.

Q: I lost my license key. Can I recover it?
A: Yes — contact us with the email you used to purchase and we'll resend it.

── ATTRIBUTION ──

Japanese vocabulary data from JMdict, © Electronic Dictionary Research and Development Group, used under CC BY-SA 3.0.