ruu-lang (รู้) turns every webpage into a personal language tutor. Highlight any word, idiom, or complex clause to get instant nuances, structural grammar breakdowns, lemma itemizations, and natural native pronunciation.
"Once in a lifetime encounter" or "Treasure every unrepeatable moment." A Zen Buddhist idiom reminding us that each gathering is unique and never happens twice.
Four-character idiom (四字熟語, yojijukugo) combining two parallel noun-number pairings with elliptical linking.
No generic translations or robotic word dumps. ruu-lang decomposes syntax and register so you genuinely understand the text.
Choose how you want it to trigger: pop the card immediately upon mouse highlight, show the floating "รู้" action badge, or use Cmd+Shift+E.
Zero vendor lock-in. Ships with Groq (openai/gpt-oss-120b) as the default, or connect your OpenAI, Anthropic Claude, Google Gemini, OpenRouter, or local Ollama/LM Studio keys. Keys are stored locally per provider, so switching presets never loses them.
Free, zero-latency pronunciation powered by the browser's on-device speech synthesis engine. Autoplays on selection or replays at any time with the R key.
Mounted inside a closed Shadow Root. Webpage scripts cannot read your card internals, and host CSS cannot distort your explanation layout.
Omit sections you don't need (Phonetics/Romanization, Grammar, Vocabulary) directly in the prompt assembly, reducing latency and model token costs.
Your API keys are stored in chrome.storage.local and never synced or transmitted to our servers. Full compliance with strict enterprise privacy policies.
From completely free tier models to state-of-the-art reasoning engines and offline local LLMs.
Try ruu-lang completely free for 3 days with all features enabled. Upgrade when you're ready.
Test all features with zero restrictions upon installation.
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