lasDoscas - YouTube™ Dual Subtitles

Watch any subtitle-enabled YouTube video with real-time bilingual subtitles. Fully customizable in font, size, and color.

Hi! This is my first Chrome extension, made with a simple goal: to make watching YouTube videos in another language a little easier and more enjoyable. lasDoscas Bilingual Subtitles shows the original and translated subtitles in sync, in real time: below the player in default view and theater mode, or at the bottom of the screen in full screen, just like native captions. Both languages, right in front of you. Free, lightweight, and built to feel right at home on YouTube. ✨ FEATURES - Dual Subtitles, Always in Sync Works on any YouTube video that has subtitles. The original text and its translation appear together in real time, so you don't lose context while watching. Subtitles resync automatically after seeking or switching caption tracks. - Manual and Auto-Generated Captions Use manually created captions or YouTube's auto-generated captions. Rolling speech-recognition captions are buffered and merged to reduce repeated words and flicker. - Smart Translation, 55 Languages Translations are generated automatically, with support for 55 target languages including English, Chinese (Simplified & Traditional), Spanish, French, German, Japanese, Korean, Arabic, Hindi, Russian, and more. On a new install, lasDoscas picks a sensible default from your browser language. - Works in Every View Fully adapted for default view, theater mode, and full-screen mode—not just the standard player. Switch views anytime and the dual subtitles adjust right along with you. - Controls Inside the YouTube Player Use the lasDoscas switch next to YouTube's own player controls to turn bilingual subtitles on or off, and select the lasDoscas icon to open settings without leaving the video. - Copy the Current Caption Hover over the subtitle panel and select the copy icon to copy the current original caption with its playback timestamp. Hold Shift while selecting it to also include the video title, publication date (when available), video link, and timestamped caption. - Fully Customizable Style Choose a global font, then show or hide either row and adjust its size, weight, and color—including in full-screen mode, which has its own font sizes plus three background modes and adjustable opacity. - Settings Save Immediately Changes apply and save on your device as soon as you make them—there's no Apply button. Reset comes with a short undo window. - Native UI Integration The subtitle cards are designed to match YouTube's own interface, with full support for both light and dark themes. - Trilingual Interface The extension popup is available in English, Simplified Chinese, and Spanish. 📖 HOW TO USE 1. Open a YouTube video that has captions. 2. In YouTube's caption menu, choose an original caption track or an auto-generated track. Don't choose YouTube's own Auto-translate track—lasDoscas needs the source caption track to create bilingual subtitles. 3. Turn on lasDoscas from the player switch or the extension popup. 4. Open settings, select your target language, and adjust the subtitle appearance. Every change takes effect immediately. ⌨️ KEYBOARD SHORTCUT Shift + Alt + S (Shift + Option + S on Mac) — quickly show or hide the subtitle style panel in full-screen mode. 🌐 COMPATIBILITY Built on Manifest V3, fully compatible with Chrome, Edge, Brave, Opera, Vivaldi, and other Chromium-based browsers. 🔒 PRIVACY FIRST lasDoscas does not collect, store, or transmit any personal data or browsing history. Your enable state, language choice, theme, and subtitle styles are saved locally on your device. Subtitle text is only sent to the translation service when a translation is actually needed. 🆓 Completely free, no ads, no sign-up required. 💡 Tip: lasDoscas only runs on YouTube video watch pages and needs an available caption track. If subtitles don't appear after selecting a track, changing videos, or reloading the extension, simply refresh the page—this usually fixes it. This is a personal project, made and maintained by one developer. If you run into any issues or have suggestions, I'd genuinely appreciate your feedback—it helps a lot. lasDoscas is an independent, open-source project and is not affiliated with or endorsed by YouTube or Google. 📋 All 55 supported target languages: English, 中文（简体）, 中文（繁体）, español, français, français (Canada), Deutsch, 日本語, 한국어, português, Indonesia, Melayu, русский, العربية, हिन्दी, தமிழ், ไทย, Tiếng Việt, Türkçe, polski, Nederlands, svenska, dansk, norsk, suomi, italiano, română, magyar, čeština, hrvatski, Ελληνικά, עברית, Filipino, українська, euskara, català, galego, íslenska, Kiswahili, eesti, latviešu, lietuvių, slovenčina, slovenščina, български, српски, اردو, فارسی, मराठी, বাংলা, ગુજરાતી, తెలుగు, ಕನ್ನಡ, മലയാളം, አማርኛ