YouTube multi-language audio (creator-uploaded dub tracks) vs automatic dubbing: eligibility via Advanced features, upload steps, localized thumbnails, copyright-mismatch removal, and YouTube's ">25% of watch time" non-primary-language claim

Per YouTube Help (R2): multi-language audio lets creators upload their own dubbed tracks (also to Shorts) and, for long-form, language-specific thumbnails; it does not generate tracks. Available to channels with Advanced features. The default track follows the viewer's preferred language (from watch history); translated titles/descriptions are used by search. Upload: Studio (desktop) > Languages > video > Add language > next to "Dub" click Add > audio-only file roughly the same length as the video > Publish. If an automatic dub exists for that language it must be deleted first. Rights warning: if the copyrighted content in a secondary track differs from the original audio, the file may be removed - so music or effects beds must match the original mix. Edits to the original (trim, audio swap) propagate to secondary tracks. Localized thumbnails: upload the main thumbnail, then add per-language thumbnails under Languages. YouTube's own claim: "Creators who uploaded Multi-language audio tracks saw over 25% of their watch time come from views in the video's non-primary language" - platform-reported, no method, sample or comparison group given, so it is not a causal uplift estimate (selection: creators who adopt dubbing likely already have international audiences). Recommended practices: depth over breadth (one or two languages, dub as much as possible, consider half or more of the back catalogue), keep translations close to the primary, add captions (auto captions are only in the original language), audio-description tracks are available to the same creators, and use Analytics broken down by audio language. Choosing between them: auto-dub is free and automatic but uneditable and limited to listed pairs; uploaded dubs (human or AI-vendor) give control over voice, terminology and mix at production cost. Curator qualifications: All cited documentation excerpts located on the live pages by curator GET; no video sources. Undated YouTube Help page as served 2026-10-23; availability changes frequently. Limitations: Undated help page; file format/bitrate limits not stated on the page (third-party guides list MP3/WAV/FLAC etc.; unverified, not used). The 25% figure is platform marketing without method. Advanced-features eligibility requirements not re-read here. Evidence status: statements located in the cited sources by a correlated desk review (Claude); not executed; not independently reviewed.

{
  "citations": [
    {
      "url": "https://support.google.com/youtube/answer/13338784?hl=en",
      "note": "What is multi-language audio?; Add a language track (Important); Key Benefits"
    }
  ]
}