ReadRiver

In-page translation of words and sentences in many languages: examples, saved words, flashcards. Free sources or your own LLM.

Reading in a foreign language breaks down every time you leave the page to look a word up. ReadRiver answers on the spot, in the page, and remembers the words worth keeping. Source code: https://github.com/alitaghiyev/readriver-extension 🖱️ Translate in place: double-click a word, select a sentence, hover a subtitle or use the right-click menu. 🏷️ One-click mode: click words while you read and their translations stay above them as small labels. 🎬 Video subtitles: hover YouTube, Netflix, video.js and native HTML5 subtitles. 🆓 Works with no key: Google Translate, MyMemory and Tatoeba example sentences are ready the moment you install. 🤖 Bring your own LLM: 18 provider presets (Gemini, Claude, OpenAI, Groq, Ollama, …) with automatic fallback. 🧠 Remember what you learn: save words and review them with Leitner flashcards. 🌍 46 languages, interface in English or Turkish. 🔒 Private by design: no server of ours, no telemetry, keys stay in your browser. 🧩 Plain JavaScript: no build step and no dependencies. ✨ Features Card mode (always on) Double-click a word to open the translation card. An optional delay keeps triple-click paragraph selection from triggering it. Select text: a small R button appears next to the selection, or the selection is translated automatically after a short delay. Can be turned off. Right-click menu: "Translate" on any selection. Modifier key (optional): translate only while Alt / Ctrl / Shift is held. Filters: min/max character count, ignore selections without letters, skip text fields, per-site block list. Works on sites that use user-select: none or put text inside buttons, and inside iframes. One-click mode (Alt+T) Turned on per tab with Alt+T or the switch in the popup; it turns off when the page reloads. The word under the mouse is highlighted; click it and the translation appears as a label right above the word. Labels stay on the page until you click the word again or press Esc. Double-click still opens the full card; links, buttons, text fields and drag-selection behave as usual. Label placement: fit between the lines, open space between the lines or overlay the line above. Colors, font size and click delay are configurable. Translation card Word, direction (e.g. EN → TR), several translations with part of speech, LLM notes and example sentences. 🔊 Pronunciation for the word and each translation, with optional auto-read. ☆ Save the word with its translation and an example sentence. Rendered inside a closed Shadow DOM, so page CSS cannot break it. Video subtitles Hover YouTube / Netflix / video.js subtitles to translate them. The video can pause while the card is open and resume when you move away. Native HTML5 <video><track> subtitles are redrawn in an overlay so each word can be hovered. Font size and background opacity are adjustable. Toolbar popup (Alt+R) Translate, History (recent translations from the cache), Saved and Review (Leitner flashcards: cards move between boxes and come back when due). Tab health: if the extension was reloaded while a page was open, the icon shows a red ! and the popup offers Reset to re-inject the scripts without reloading the page. Settings and maintenance Persistent cache with a configurable size. Usage counter: requests, errors, characters and tokens per source, per day, for the last 90 days. Backup: export and import settings, providers and saved words as JSON. API keys are left out unless you choose to include them. Diagnostics: background worker, reachability of each source, whether the content script runs on the current page, last translation. What's new in 0.10.8 • Subtitle hover no longer pauses the video or translates the player's settings menu and controls (YouTube and others). • One-click mode labels are larger by default (15 px) and no longer shrink below 11 px. • The free provider's name now follows the interface language ("Fast (free)" / "Hızlı (ücretsiz)").