Vocaboo

Learn English vocabulary from selected words, phrases, and paragraphs while browsing.

Turn everyday browsing into effortless English vocabulary learning. Vocaboo helps you understand and remember the words and phrases you encounter online. Highlight anything on any web page and instantly get a clear, AI-powered explanation — then save it and lock it into long-term memory with proven spaced repetition. How it works • Select any word, phrase, or paragraph on any page. • Click the Vocaboo button (or right-click → "Explain selection"). • Get an instant explanation of the passage plus the most useful vocabulary inside it — with definitions, pronunciation, in-context meaning, difficulty, and example sentences. • Save words to your personal library with one click. Remember what you learn • Built-in spaced-repetition system (SM-2) schedules reviews at the perfect time. • Multiple-choice quizzes reinforce meaning. • Track your daily streak, mastery progress, and CEFR level on a clean, distraction-free dashboard. Private by design • Everything is stored locally in your browser — no account required. • No tracking, no analytics, no ads. • The bundled offline AI works without any setup. Prefer higher-quality results? Connect your own OpenAI, Azure OpenAI, or custom endpoint — your API keys are encrypted at rest (AES-GCM-256). Made for Self-directed learners, ESL students, exchange students, and anyone reading English articles, documentation, or news.