pf

A modern CLI tool to identify and manage processes using network ports.
Built with Go for speed, clarity, and zero runtime dependencies.

🎬 Preview

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✨ Features

• 🔍 Smart Process Detection — Instantly find what's using your ports
• 📁 Project Awareness — Shows which project/directory owns the process
• 🐳 Docker Support — Identifies containerized processes
• 🎯 Quick Actions — Kill processes interactively or directly
• 📊 Port Overview — Check all common development ports
• 🚀 Fast & Lightweight — Single binary, no runtime dependencies

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📦 Installation

✅ Using Homebrew (macOS/Linux)

brew tap doganarif/tap
brew install pf

🪟 Windows

Download the latest .exe file from the Releases Page:

• For 64-bit Windows: pf-windows-amd64.exe
• For ARM64 Windows: pf-windows-arm64.exe

Rename it to pf.exe and add to your PATH.

🧰 Using Go

go install github.com/doganarif/portfinder/cmd/portfinder@latest

This installs the binary as pf.

📁 Download Binary

Grab the latest release from the Releases Page.

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🧪 Usage

🔍 Check a specific port

pf 3000

Output:

🔍 Port 3000 is in use by:

Process     node
PID         48291
Command     npm run dev
Project     ~/projects/my-react-app
Started     3 hours ago

Kill this process? [y/n]

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📊 Check common development ports

pf check

Example output:

📊 Common Development Ports:

Frontend:
  ❌ 3000: node (my-react-app)
  ✅ 3001: free
  ✅ 4200: free
  ❌ 5173: vite (my-vue-app)
  ✅ 8080: free

Backend:
  ✅ 4000: free
  ❌ 5000: python (flask-api)
  ✅ 8000: free
  ✅ 9000: free

Databases:
  ✅ 3306: free
  ❌ 5432: postgres (docker)
  ❌ 6379: redis
  ✅ 27017: free

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📋 List all ports in use

pf list

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💀 Kill a process

pf kill 3000

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⚙️ Common Ports Reference

Port	Common Use
3000	React, Node.js, Rails
3001	Create React App fallback
4200	Angular
5173	Vite
5000	Flask, Python servers
8000	Django
8080	General web development
3306	MySQL/MariaDB
5432	PostgreSQL
6379	Redis
27017	MongoDB
9200	Elasticsearch
9090	Prometheus
3100	Grafana Loki
8983	Solr

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🛠️ Configuration

You can override the default list of common ports by creating a config file at:

~/.config/portfinder/config.json

Example:

{
  "common_ports": [3000, 3001, 5173, 5000, 8000]
}

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🧑‍💻 Development

Prerequisites

• Go 1.21+
• Make (optional)

Building from source

# Clone the repository
git clone https://github.com/doganarif/portfinder.git
cd portfinder

# Build
make build

# Run tests
make test

# Install locally
make install

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📁 Project Structure

pf/
├── cmd/
│   └── portfinder/     # CLI entry point
├── internal/
│   ├── config/         # Configuration management
│   ├── process/        # Process detection logic
│   └── ui/             # Terminal UI components
├── Makefile            # Build automation
└── README.md           # This file

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🤝 Contributing

Contributions are welcome! Please open an issue or pull request.

1. Fork the repository
2. Create your feature branch (git checkout -b feature/amazing-feature)
3. Commit your changes (git commit -m 'Add amazing feature')
4. Push to the branch (git push origin feature/amazing-feature)
5. Open a Pull Request

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📜 License

This project is licensed under the MIT License — see the LICENSE file.

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🙌 Acknowledgments

• Inspired by the frustration of "port already in use" errors
• Built using Cobra for CLI
• Terminal UI powered by Bubbletea

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🧑 Author

Arif Doğan

• GitHub: @doganarif
• Twitter: @arifcodes

If you find this tool useful, please consider giving it a ⭐️ on GitHub!

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Built by Arif Dogan - production AI and backend engineer.

I help SaaS teams ship production AI features, fast backends, and reliable developer tools.

Work with me | Book a 30-min intro