Privacy policy

Subtitles Unbound browser extension · last updated 29 October 2026

Subtitles Unbound collects no personal data. It has no account, no analytics, no ads and no tracking, and it sells or shares nothing.

What stays on your computer

Your subtitle files, your settings, the OpenSubtitles API key you enter, and everything live captions and Auto-sync hear. The sound of the video is processed by the speech engine inside your browser and is never sent anywhere. Settings and downloaded speech models are kept in your browser's own storage; removing the extension deletes them.

What is sent, and only when you use the feature

• Find subtitles. When you press Find, the search text, the chosen language and your OpenSubtitles API key go to api.opensubtitles.com. If the page plays a plain video file, a short fingerprint of that file goes too (the OpenSubtitles hash, made from the file's size and its first and last 64 KB; it can't be turned back into the video). Downloading a result fetches it from OpenSubtitles. Their privacy policy applies to these requests.
• Speech models. The first time you turn on live captions, the speech model is downloaded from alphacephei.com (Vosk) or huggingface.co (Whisper). Nothing about you or what you watch is sent with that download.

Why it asks for access to all websites

So it can show subtitles on whatever site plays your video. On those pages it only looks for the video player, its size and its playback time, and adds its own subtitle layer. It doesn't read or send the page's content. It can listen to the video's sound only to make live captions or Auto-sync when you turn them on.

Contact

Questions: hello@subtitlesunbound.com.