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asbplayer

Open-source subtitle tool that makes selectable subtitles and Anki cards from video.

Last updated November 2026

About asbplayer

asbplayer is a subtitle player built for sentence mining, the habit of learning a language by collecting full sentences from shows you enjoy. It makes subtitles on a video selectable text, so a dictionary tool can look up any word. It then turns a line into an Anki flashcard that includes the audio and a screenshot from the scene.

It works on two kinds of video. On popular streaming sites such as Netflix and YouTube it detects the subtitles automatically. For other sites, its README says a fallback detector finds subtitles on about 85 per cent of them, and you can always load your own subtitle files. It can also colour words by how well you know them, using data from Anki or WaniKani. The project is open source under the AGPL, and the developer's listing says it will not collect or use your data.

The cost is setup. Its own guide has you install a dictionary extension such as Yomitan, install Anki, add the AnkiConnect plugin and then configure asbplayer to use your deck. It does not translate for you or teach, so it suits learners who already follow a method. If that is you, it is the best free way to turn video into flashcards.

Pros and cons

  • Free and open source, and declares it collects no data
  • Detects subtitles on Netflix and YouTube, or loads your own files
  • Builds Anki cards with audio and screenshots from the scene
  • In Firefox as well as Chrome
  • Needs Anki, AnkiConnect and a dictionary tool to set up
  • Aimed at committed learners, not casual viewers
  • No translations or lessons of its own

Permissions

It asks for access to all websites so it can find and display subtitles on any video page, plus tabs, storage and tab-capture permissions.