YouTube Transcript Downloader

Export YouTube captions as clean text, Markdown, SRT, or JSON — with timestamps, translations, and AI-ready context.

Chrome · Edge · Brave · Opera · Vivaldi · Firefox · Safari source

What it does

YouTube Transcript Downloader adds a focused transcript panel beside supported YouTube videos and a compact Transcript button below the player. It discovers captions automatically, selects the video’s original language when available, and lets you export the complete transcript in the format you need.

Automatic discovery	Original-language first
Finds caption tracks as soon as a video opens, with honest loading progress and a Retry action when needed.	Uses the video’s source audio language instead of a browser-localized dub whenever YouTube exposes that metadata.
Five export formats	Translation on demand
Structured text, Markdown, plain text, SRT subtitles, and JSON with timestamps and video metadata.	Optionally requests a selected target language through YouTube’s Google-powered caption translation.
Playback-following preview	Ready for AI workflows
Highlights the sentence being spoken and keeps it in view as the video plays.	Add export title, content type, tags, and AI instructions. Saved preferences are restored automatically.

Install

Chrome, Edge, Brave, Opera, Vivaldi, and other Chromium browsers

1. Download or clone this repository.
2. Open your browser’s extension management page:
   • Chrome / Brave / Vivaldi: chrome://extensions
   • Edge: edge://extensions
   • Opera: opera://extensions
3. Enable Developer mode.
4. Choose Load unpacked.
5. Select the project folder, or select dist/chromium after running the build.
6. Open a YouTube watch page and refresh it once.

Firefox

1. Run npm run build.
2. Open about:debugging#/runtime/this-firefox.
3. Select Load Temporary Add-on.
4. Choose dist/firefox/manifest.json.

Temporary add-ons are removed when Firefox restarts. Permanent Firefox distribution requires signing through Mozilla.

Safari

Safari requires Apple’s Safari Web Extension Packager and Xcode. First run npm run build, then follow Safari packaging instructions.

Use it

1. Open a YouTube video with captions.
2. Wait while the extension searches for tracks. The progress bar is indeterminate while discovery is underway, then becomes a real percentage only when YouTube provides measurable download progress.
3. Check Video language. The original video language is selected automatically; choose another available track if you prefer.
4. Optional: enable Translate before downloading and choose a target language.
5. Review the interactive transcript. Clicking a row seeks the video to that sentence.
6. Choose an export format. A preview shows the first five transcript entries exactly as they will be exported.
7. Open Advanced export if you want to include AI context, tags, content type, or a custom title. These values are saved locally for next time.
8. Click the export button to download the complete transcript.

Export formats

Format	Best for	Includes
Structured text	Reading or quoting	Start and end timestamps
Markdown	Notes and documentation	Timestamped Markdown list and metadata
Plain text	Clean copy/paste	Transcript text only, or optional metadata
SRT	Video editing and players	Standard subtitle timing
JSON	Apps, automations, and AI	Segments, metadata, timestamps, and export context

Preferences and privacy

• Interface language: English, Brazilian Portuguese, or French, with browser-language detection.
• Appearance: follow system, light, or dark.
• Advanced export options and UI preferences are saved only in the browser’s local extension storage.
• The extension reads caption data exposed by the active YouTube watch page. It does not store account cookies, authorization headers, visitor IDs, or captured network requests.

Develop

npm test
npm run build

npm test runs unit, integration, regression, storage compatibility, and package-build checks. Every bug fix should include a regression test.

npm run build creates browser-ready folders in dist/:

• dist/chromium
• dist/opera
• dist/firefox
• dist/safari-source

Troubleshooting

Problem	What to try
“Looking for available subtitles…”	Wait briefly. If discovery takes eight seconds, use Retry. Confirm the video has captions.
No caption track is found	Open YouTube’s native transcript panel once, then try Retry. Some videos have no captions.
The extension does not appear	Reload the unpacked extension and refresh the YouTube watch page.
Translation is unavailable	The selected YouTube caption track may not support translated tracks. Choose another source track or export the original.

Project structure

content.js       Extension panel UI and export flow
page-bridge.js   YouTube caption discovery and loading bridge
core.js          Shared, browser-neutral transcript and export logic
styles.css       Panel styling and themes
icons/           Logo, favicon, and extension icons
test/            Unit, integration, regression, and build tests
scripts/         Cross-browser package builder

YouTube is a frequently evolving site. If YouTube changes its internal caption structures, update the extension, reload it in your browser, and refresh the watch page.