Immerse Japanese — Learn Japanese While Browsing

Tracking since Apr 7, 2026.

Changelog

• May 25, 2026
  description

  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.

  LEARN JAPANESE WHILE YOU BROWSE THE WEB
  
  Immerse Japanese turns your everyday browsing into passive Japanese practice. As you read English articles, news, Wikipedia pages, or YouTube subtitles, words are automatically replaced with their Japanese translations — kanji, kana, and romaji — right on the page. No flashcard apps to open. No studying sessions to schedule. Just browse, and absorb.
  
  Too busy to open a Japanese textbook? This is your answer. Browse in English, notice a Japanese word you don't know, save it with one click, and review it later with built-in spaced repetition. The words come to you — you don't have to go looking for them.
  
  ──────────────────────────────────────
  HOW IT WORKS
  ──────────────────────────────────────
  
  Immerse Japanese works silently in the background on every website you visit. At the replacement rate you choose, English words are swapped with Japanese. Hover any replaced word to reveal a popup showing:
  
  • The Japanese word (kanji + kana + romaji)
  • The English meaning
  • JLPT level badge (N5, N4, N3, N2, N1 and News vocabulary)
  • Alternative translations with their own JLPT levels
  • Example sentences from Tatoeba
  • Save button to add to your personal word list
  
  ──────────────────────────────────────
  KEY FEATURES
  ──────────────────────────────────────
  
  ✦ Works on any website — news, blogs, Wikipedia, Reddit, social media
  ✦ Works on YouTube subtitles — replaces words live in captions while you watch (Premium)
  ✦ 11,000+ English words mapped to Japanese; 22,000+ Japanese entries in the popup
  ✦ JLPT-aware — filter by N5, N4, N3, N2, or N1 to match your study level
  ✦ News vocabulary — includes contemporary words beyond JLPT levels for real-world reading
  ✦ Multiple display modes: romaji, kana, kanji, kanji+kana, or English highlighted
  ✦ Color-by-level highlighting so you can see difficulty at a glance
  ✦ First occurrence only mode — replaces each word once per page to reduce clutter
  ✦ Adjustable replacement rate — replace words partially to avoid seeing too many translations
  ✦ Body text only mode — skips navigation, buttons, and UI clutter from translation
  ✦ Ignore list — hide words you already know
  
  ──────────────────────────────────────
  SAVE WORDS & REVIEW WITH SPACED REPETITION
  ──────────────────────────────────────
  
  Click "+ Save" on any word in the popup to add it to your personal vocabulary list. The complete learning loop, without leaving your browser:
  
  1. Browse any English page normally
  2. See a Japanese word you don't know — hover for the full definition
  3. Save it with one click
  4. Review it later in the built-in flashcard system using spaced repetition
  5. The word moves into long-term memory
  
  Already use Anki? Premium users can export their saved words directly to Anki and slot them into their existing deck.
  
  ──────────────────────────────────────
  JLPT COVERAGE
  ──────────────────────────────────────
  
  The dictionary is sourced from JMdict, the gold standard open Japanese dictionary, filtered and curated for learner quality. Every word is tagged with its JLPT level:
  
  • N5 — Core ~600 words (beginner) — FREE
  • N4 — Common ~1,500 words — Premium
  • N3 — Intermediate ~3,750 words — Premium
  • N2 — Upper-intermediate ~6,000 words — Premium
  • N1 — Advanced 10,000+ words — Premium
  • News & contemporary vocabulary — words beyond JLPT used in real-world articles, news, and media — Premium
  
  Enable only the levels you're studying — the extension will only replace words at or below your chosen level. Start free with N5 and upgrade when you're ready.
  
  ──────────────────────────────────────
  PRICING
  ──────────────────────────────────────
  
  Free — no account needed, no time limit:
  • JLPT N5 vocabulary
  • All display modes (romaji, kana, kanji, English highlighted)
  • Save words & spaced repetition review
  
  Premium — one-time purchase, no subscription:
  • Everything in Free, plus:
  • N4, N3, N2, N1, and news vocabulary — full 11,000+ word coverage
  • YouTube subtitle support
  • Anki export
  
  ──────────────────────────────────────
  FREQUENTLY ASKED QUESTIONS
  ──────────────────────────────────────
  
  Q: Does this work on YouTube?
  A: Yes. Immerse Japanese replaces words directly inside YouTube subtitles as they appear on screen.
  
  Q: Will it slow down my browser?
  A: No. The dictionary is loaded once and cached locally. Replacements happen instantly with no network requests.
  
  Q: What is the best Chrome extension to learn Japanese while browsing?
  A: Immerse Japanese is designed specifically for passive immersion — unlike lookup tools like Yomichan, it replaces words automatically so you absorb Japanese without changing how you browse.
  
  Q: Is it different from Yomichan or Rikaikun?
  A: Yes. Yomichan and Rikaikun are lookup tools — you hover over Japanese text to see a definition. Immerse Japanese works the opposite way: it replaces English words with Japanese on any page you visit, so you learn while reading English content.
  
  Q: Can I use this as a complete beginner?
  A: Yes. Start with JLPT N5 (the free tier) to see only the most fundamental Japanese words. Upgrade to unlock more vocabulary as you progress.
  
  Q: How many Japanese words does it cover?
  A: Over 11,000 English words are mapped to Japanese translations. The hover popup draws from a database of 22,000+ Japanese entries to show alternative translations and meanings.
  
  Q: Does it support romaji for beginners who can't read kana yet?
  A: Yes. Choose from romaji, kana, kanji, or kanji+kana display modes. You can also use English highlighted mode — keeps English on the page but highlights replaced words; hover to reveal the Japanese.

• May 25, 2026
  short_description

  Learn Japanese while you browse. Words swap to Japanese — hover to reveal kanji, kana, romaji. Free for N5. No subscription.

  Learn Japanese passively as you browse — English words swap to Japanese automatically. Hover for kanji, kana, romaji. Free for N5.

• May 1, 2026
  host_permissions

  <all_urls>, https://immerse-japanese-worker.clearsight.workers.dev/*

  <all_urls>, https://license-api.clearsight.workers.dev/*

Permissions & access

Permissions

storagealarmsdownloadstabs

Host access

<all_urls>, https://license-api.clearsight.workers.dev/*

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