Angular Dev Server
What is Port 4200?
Port 4200 is the default port for the Angular CLI development server (ng serve). Angular, developed and maintained by Google, is one of the most popular frontend frameworks for building single-page applications. When you run ng serve, the Angular development server starts on port 4200 with hot module replacement, automatic recompilation, and live reload. The development server also includes a built-in proxy configuration for forwarding API requests to backend servers, making it easy to develop full-stack applications. Port 4200 is exclusively associated with Angular development and is rarely used in production, where Angular applications are built into static files and served by Nginx or similar web servers.
Common Uses
- Angular application development and testing
- Angular CLI development server (ng serve)
- Hot module replacement during development
- Proxied API development with Angular CLI
Technical Details
Copy-paste commands to check port 4200 (Angular Dev Server) from your terminal
Test connectivity
nc -zv example.com 4200
curl -v --max-time 5 http://example.com:4200/
telnet example.com 4200
nmap -p 4200 -sV example.com
(echo > /dev/tcp/example.com/4200) 2>/dev/null && echo "open" || echo "closed"
Open port in firewall
sudo ufw allow 4200/tcp
sudo iptables -A INPUT -p tcp --dport 4200 -j ACCEPT
sudo firewall-cmd --permanent --add-port=4200/tcp && sudo firewall-cmd --reload
Security Considerations
The Angular dev server is intended for development only and should never be used in production. It may expose source maps, detailed error messages, and debugging information. Always build Angular for production (ng build --configuration production) and serve the static output with a proper web server. Bind to localhost during development.
Popular Ports Reference
The most commonly used and referenced network ports