Word-by-word translation
Hover any subtitle word to see its exact meaning without pausing or opening a new tab.
Sublern
Sublern is a free Chrome extension for language learners that translates subtitle words in video players, showing meaning, pronunciation, and examples without leaving playback.
Overview
Sublern is a Chrome extension for language learners that adds instant subtitle translation to video platforms. It lets you hover a word in subtitles to see its meaning, pronunciation, and usage examples directly on top of the video.
The product is positioned for watching with subtitles on supported platforms such as YouTube, Netflix, TED, Udemy, Twitch, Plex, and Jellyfin, with automatic activation and no account required. The site also states that translations are processed on demand and that the extension is free to use.
Features
Real-world examples
View three example sentences drawn from native content to understand how a word is used in context.
Text-to-speech pronunciation
Hear any word spoken aloud with a native voice by clicking the pronunciation control.
Auto-pause on hover
Let the video pause automatically while you read, then resume when you move on.
Customizable interface
Adjust interface details such as font size, tooltip position, colors, background opacity, and example count.
Vocabulary tools and shortcuts
Save words from the tooltip to a personal dictionary for later review, and use keyboard shortcuts for common actions.
Use Cases
Language learning during streaming
Watch films, series, or tutorial videos and translate unfamiliar subtitle words without leaving playback or losing the scene.
Vocabulary building with context
Use the hover translation, pronunciation, and example sentences to study how a word is used in context while you watch.
Fullscreen viewing
Read subtitles in fullscreen or picture-in-picture when you want to keep the video large but still inspect a word quickly.
Self-study and review
Review saved words later from the personal dictionary after a viewing session, instead of relying on memory alone.
Supported platform playback
Watch on supported services and embedded players that use common video engines, including Video.js, Shaka Player, and Playerjs.
Pros and Cons
Pros
- Hover-based translation keeps the video in view and avoids opening a separate tab.
- Example sentences, pronunciation, and auto-pause combine translation with learning context.
- The extension supports many major streaming platforms and several embedded players.
- The interface is available in 20+ languages and translations are available in 30 languages.
- The site says there is no account requirement and no ads.
Cons
- Support is described by the site as limited to platforms with subtitle playback and to listed players or sites using supported video engines.
- The pricing page is unavailable, so the public site does not provide plan-level detail beyond the claim that the extension is free.
- The page does not describe offline use or broader browser compatibility outside Chrome.
FAQ
Which streaming platforms are supported?
Sublern works on YouTube, Netflix, TED, Udemy, Rutube, Disney+, Prime Video, Twitch, Plex, Jellyfin, and sites using Video.js, Shaka Player, or Playerjs.
Does it work in fullscreen mode?
Yes. The tooltip is designed to work in fullscreen mode and picture-in-picture mode.
What languages can I translate to?
Sublern supports translation into 30 languages, and the interface is available in 20+ languages including English, Russian, Ukrainian, German, French, and Spanish.
Does it store my data?
No. The site says translations are processed on demand and that nothing about your viewing history is stored or sent to a server it controls.
Is it really free?
Yes. The product page says Sublern is free, requires no account, and has no premium tier or ads.
Quick Facts
- Category
- Chrome extension, language learning
- Platform
- Chrome
- Primary use
- Subtitle word translation while watching video
- Supported services
- YouTube, Netflix, TED, Udemy, Rutube, Disney+, Prime Video, Twitch, Plex, Jellyfin, and selected players
- Translation languages
- 30
- Interface languages
- 20+ languages
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