Speak Subtitles for YouTube
Reads YouTube subtitles out loud with synthetic voices in many languages, so you can listen to a video instead of reading captions.
Chrome extension
Reads YouTube subtitles aloud with synthetic voices in many languages, for viewers who would rather listen than read captions.
YouTube Subtitles Speaker reads a video's subtitles aloud using text-to-speech voices. It is for viewers who would rather listen than read captions, including when watching videos in languages they do not speak.
Pin the extension, open a YouTube video with subtitles and click the voice icon that appears, then pick your voice language.
It only works on YouTube videos that have subtitles. The voices are generated by third-party speech services from Google and Microsoft.