YouTube Transcript Summarizer

Extract transcripts from YouTube videos and generate AI-powered summaries. Supports any source language and can output summaries in your preferred language.

Requirements

pip install -r requirements.txt
# or: pip install youtube-transcript-api anthropic

• ANTHROPIC_API_KEY env var required for AI summarization
• yt-dlp (optional) for automatic video title fetching
• Python 3.7+

Cost depends on transcript length and current Claude API pricing.

Usage

# Single video (default: English -> Korean)
python youtube_transcript_summarizer.py "https://www.youtube.com/watch?v=VIDEO_ID"

# Transcript only (no AI summary)
python youtube_transcript_summarizer.py "VIDEO_URL" --no-summary

# Japanese video with English summary
python youtube_transcript_summarizer.py "VIDEO_URL" --source-lang ja --target-lang en

# Auto-detect source language
python youtube_transcript_summarizer.py "VIDEO_URL" --source-lang auto --target-lang fr

# Batch processing
python youtube_transcript_summarizer.py --batch "urls.txt" --output-dir "summaries"

# Custom model and transcript limit
python youtube_transcript_summarizer.py "VIDEO_URL" --model claude-sonnet-4-5-20250929 --max-transcript-chars 30000

CLI Options

Option	Description	Default
--title	Custom video title	Auto-fetched via yt-dlp
--source-lang	Source transcript language	en
--target-lang	Output summary language	ko
--output-dir	Output directory	outputs/summaries
--batch FILE	Process multiple URLs from file	-
--timeline-interval	Timeline interval (minutes)	5
--no-summary	Skip AI summary	false
--api-key	Claude API key	ANTHROPIC_API_KEY env
--model	Claude model name	claude-sonnet-4-5-20250929
--max-transcript-chars	Max chars sent to Claude	15000

Supported Languages

en, ko, ja, zh, es, fr, de, pt, ru, ar, hi, auto

Output Format

Files are named YYYY-MM-DD VideoTitle.md with YAML frontmatter:

---
title: "Video Title"
source: "https://www.youtube.com/watch?v=ID"
created: YYYY-MM-DD HH:MM:SS
tags:
  - youtube-transcript
video_id: "ID"
source_lang: "en"
target_lang: "ko"
---

Sections: Summary, Key Points, Main Content, Timeline, Full Transcript.

Claude Code Integration

Summarize this YouTube video: https://www.youtube.com/watch?v=VIDEO_ID