Stop Port 3000 Mac
sudo lsof -i :3000
kill -9 PID
Ghaith Alzin
sudo lsof -i :3000
kill -9 PIDsudo lsof -i tcp:3000
lsof -n -i TCP:8080
COMMAND PID USER FD TYPE DEVICE SIZE/OFF NODE NAME
node 54762 user 23u IPv4 XXXXXXXXX 0t0 TCP 127.0.0.1:http-alt (LISTEN)
PID // is second field in the response . Then, kill that process:
kill -9 54762 // here put PID number found on the table 54762kill $(lsof -ti:3000,3001,8080)