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How it works: YouTube Caption Bot

For turning a video into text you can read, search and quote, instead of scrubbing through it.

Philosophy

  • Use the captions that already exist. The tool doesn't transcribe audio; it fetches the captions a video already has, which is fast, free and faithful to what was said.
  • Prefer captions a person wrote. Creator-uploaded captions win over automatic ones, and a badge always says which kind the transcript came from.
  • English first, never a surprise language. When a video offers many translated caption tracks, the tool picks English rather than whichever happens to be listed first.
  • Say plainly when there's nothing. A video without captions gets a clear message, not a blank box or a silent failure.
  • Local by design. The tool and its history run on one machine; anything shown in public uses made-up demo videos.

The workflow

YouTube Caption Bot: the workflow as a flowchart1Paste a video linkany common YouTube link format works.owner2Find the videoread the video's ID from the link and fetch its title, channel andthumbnail.tool3List its caption trackscreator-uploaded and automatic, in every language offered.tool4Pick the best trackcreator captions over automatic ones, English over other languages.tool5Show the transcriptthe full text, with a badge naming which captions were used.tool6Save it to historyso it's one click away next time; re-reading a video replaces itsentry.tool7Copy and use itone button copies the title, channel and text, ready to paste.ownerNo captions at allAn oldertranscriptYouTube Caption Bot: the workflow as a flowchart1Paste a video linkany common YouTube link format works.owner2Find the videoread the video's ID from the link andfetch its title, channel and thumbnail.tool3List its caption trackscreator-uploaded and automatic, in everylanguage offered.↩ No captions at all → step 1tool4Pick the best trackcreator captions over automatic ones,English over other languages.tool5Show the transcriptthe full text, with a badge naming whichcaptions were used.tool6Save it to historyso it's one click away next time;re-reading a video replaces its entry.tool7Copy and use itone button copies the title, channel andtext, ready to paste.↩ An older transcript → step 7owner

What it owns

  • The caption tool itself: a link goes in, the transcript comes out, and it copies with its title and channel.
  • The local history of past transcripts, with thumbnails, channel and date.
  • A demo set of invented videos, so every public screenshot shows the real tool on made-up content.
  • Its own devlog entries and this page.

What it hands off

  • Art Director: the tool's mark, icons and colours; the tool uses them unchanged.
  • Project Manager: studio rules, shared tools, and routing decisions.
  • NeptuneVibes.com Web Dev: publishing the devlog and this page.

Guardrails

  • Reads captions only; never downloads video or audio.
  • Runs locally; the history stays on the machine, and nothing is uploaded or sent.
  • Public screenshots use invented demo videos only, never real viewing history.
  • Never uses YouTube's logo or play badge as its own mark.

At work

The transcribe flow on the demo set: a link goes in, the transcript appears with its caption badge, and Copy confirms.

The transcribe flow on the demo set: a link
goes in, the transcript appears with its caption badge, and Copy confirms.