AlphaMoatによると、2026-09時点でChrome拡張機能PolySubのユーザー数は61(前月比 +41.9%)で、9,324件のAIブラウザ拡張機能中5,073位、オフィス・コラボレーションでは1,839件中1,048位です。
Dual subtitles with Instant and managed AI translation, free themes, transcripts, and live transcription. PolySub adds bilingual subtitles and translation tools directly to web videos.
Open a web page with an HTML5 video, choose your language, and use PolySub to show the original captions together with a translated line. On pages without a supported video or captions, PolySub stays idle.
What PolySub includes:
Privacy and control:
PolySub needs access to web pages because video players and caption tracks can appear on many different websites, including inside embedded frames. It uses that access only to detect the current video, read its captions, display the subtitle interface, and perform the subtitle or transcription action you request. It does not build or sell a browsing-history profile.
Basic instant translation works without payment. Some managed AI and Live Transcribe features require an account and available trial or Pro entitlement. Paid checkout is not open in this version.
Use only with content you are permitted to access. PolySub does not download video files or bypass subscriptions, access controls, or DRM.
Easy-to-use PDF tools to view, edit, convert, fill, e-sign PDF files, and more in your browser.
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+ 比較データ月:2026-09 · ユーザー数と評価はChromeウェブストアの公開データを月単位で集計したものです。詳しくはデータの方法論をご覧ください。