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💡 Pro Tip: Port 4201 is commonly used as a backup when port 4200 is already in use by another Angular application or development server.

Quick Commands for Angular Port 4201

Start Angular on port 4201:
ng serve --port 4201
npm start -- --port 4201

Find what's using port 4201:
lsof -i :4201 (Mac/Linux)
netstat -ano | findstr :4201 (Windows)

Kill process on port 4201:
kill -9 $(lsof -t -i:4201) (Mac/Linux)
for /f "tokens=5" %a in ('netstat -aon ^| findstr :4201') do taskkill /PID %a /F (Windows)

Check Angular version:
ng version
npm list @angular/core

About Port 4201

Port 4201 is commonly used for:

Angular backup - When port 4200 is busy
Multiple Angular apps - Running simultaneously
Development testing - Different versions
Ionic backup - Mobile app development
Angular workspaces - Multiple projects

Common Use Cases

Running multiple Angular applications during development
Testing different versions of the same Angular app
Micro-frontends architecture with multiple Angular apps
Angular workspace with multiple projects
Development and testing environments running in parallel

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Did you mean to visit localhost:4201?

Quick Commands for Angular Port 4201

About Port 4201

Common Use Cases

Related Angular & Frontend Ports