YouTube Video Summarizer with Gemini API

A Python tool that uses Google's Gemini API to automatically summarize YouTube videos.

Features

• 🎥 Summarize any YouTube video using AI
• 🌐 Multi-language support (Chinese, Spanish, French, etc.)
• 🚀 Support for multiple Gemini models
• 🎨 Beautiful CLI output with progress indicators
• 💾 Save summaries to file
• 🔧 Custom prompt support
• 🔐 Environment variable support for API keys

Setup

1. Install dependencies:

pip install -r requirements.txt

2. Set up your Gemini API key:
   • Copy .env.example to .env
   • Add your Gemini API key to the .env file
   • Or set it as an environment variable: export GEMINI_API_KEY=your_key_here

Usage

Basic usage:

python youtube_summarizer.py "https://www.youtube.com/watch?v=VIDEO_ID"

With custom prompt:

python youtube_summarizer.py "https://www.youtube.com/watch?v=VIDEO_ID" --prompt "Summarize this video in 3 bullet points"

Save to file:

python youtube_summarizer.py "https://www.youtube.com/watch?v=VIDEO_ID" -o summary.txt

Use different model:

python youtube_summarizer.py "https://www.youtube.com/watch?v=VIDEO_ID" --model gemini-2.5-flash

Summarize in different languages:

# Chinese
python youtube_summarizer.py "https://www.youtube.com/watch?v=VIDEO_ID" --lang zh
python youtube_summarizer.py "https://www.youtube.com/watch?v=VIDEO_ID" --lang chinese

# Spanish
python youtube_summarizer.py "https://www.youtube.com/watch?v=VIDEO_ID" --lang spanish

# French
python youtube_summarizer.py "https://www.youtube.com/watch?v=VIDEO_ID" -l fr

With API key flag:

python youtube_summarizer.py "https://www.youtube.com/watch?v=VIDEO_ID" --api-key YOUR_API_KEY

Examples

1. Summarize a tech tutorial:

python youtube_summarizer.py "https://www.youtube.com/watch?v=dQw4w9WgXcQ" \
  --prompt "Extract the main steps and technical concepts from this tutorial"

2. Get key takeaways from a lecture:

python youtube_summarizer.py "https://youtu.be/VIDEO_ID" \
  --prompt "List the main concepts discussed and any important definitions"

3. Create study notes:

python youtube_summarizer.py "https://youtube.com/watch?v=VIDEO_ID" \
  --prompt "Create detailed study notes with headings and bullet points" \
  -o lecture_notes.txt

4. Get summary in Chinese:

python youtube_summarizer.py "https://youtube.com/watch?v=VIDEO_ID" \
  --lang zh \
  -o chinese_summary.txt

5. Combine custom prompt with language:

python youtube_summarizer.py "https://youtube.com/watch?v=VIDEO_ID" \
  --lang chinese \
  --prompt "用三个要点总结这个视频的核心内容"

Supported URL Formats

• https://www.youtube.com/watch?v=VIDEO_ID
• https://youtu.be/VIDEO_ID
• https://youtube.com/watch?v=VIDEO_ID&t=123s
• https://www.youtube.com/embed/VIDEO_ID

Supported Languages

The tool supports multiple output languages. Use the --lang or -l flag:

• Chinese: zh, cn, chinese
• English: en, english (default)
• Spanish: es, spanish
• French: fr, french
• German: de, german
• Japanese: ja, japanese
• Korean: ko, korean
• Or specify any other language by name

Requirements

• Python 3.8+
• Valid Gemini API key
• Internet connection

Notes

• The tool uses gemini-2.5-flash model by default (fast and efficient)
• For more detailed summaries, you can specify different models with --model flag
• API usage is subject to Google's rate limits and pricing