Lingoku

What it does

Lingoku is a browser extension that helps you learn Japanese naturally while watching anime, reading news, or browsing any website. It adds furigana readings above kanji, provides AI-powered context-specific meanings on hover, and distinguishes keigo politeness levels. You can save words with one click to create flashcards that include the original sentence, AI explanation, and JLPT level. The extension uses spaced repetition to resurface words before you forget them.

Who it is for

Lingoku is designed for Japanese learners of all levels who want to learn from real content rather than textbooks. It's especially useful for anime and J-drama fans, people preparing for JLPT (N5-N1), Chinese speakers who need help with false friends, and professionals reading Japanese news or technical documents. The tool works on Netflix, YouTube, Bilibili, Reddit, Twitter/X, Hacker News, and any website with Japanese text.

Why it matters

Traditional language learning relies on rote memorization and isolated drills, which often fail to stick. Lingoku leverages decades of linguistics research on comprehensible input (i+1) — you acquire language best from content slightly above your level. Words encountered in emotionally engaging scenes have 3x better retention than flashcards. The AI identifies which kanji are new to you (i+1) and skips those you already know, keeping your reading flow smooth. Spaced repetition fights the forgetting curve by resurfacing words at optimal intervals.

Launch signal

Lingoku was launched on Hacker News as a Show HN post titled "Learn Japanese contextually while browsing." The website claims over 1 million users and a 4.9 rating on the Chrome Store, though these metrics are not independently verified. The extension is free with a basic plan forever, no credit card required. It supports 50+ platforms and offers a 30-second install with no sign-up needed.

Brand and naming

The name "Lingoku" blends "lingo" (language) with "-ku" (possibly from "gaku" meaning learning or a nod to Japanese). It's short, memorable, and suggests a focus on language acquisition. The brand positions itself as a natural, effortless alternative to traditional apps like Wanikani, Anki, or Jisho. The tagline "Master Japanese Through Anime & Netflix" clearly targets anime fans, a large and passionate audience. The design is clean and modern, with a strong emphasis on user testimonials and comparison tables to build credibility.