Port 5432 (PostgreSQL)
Port 5432 is the default port of PostgreSQL. Applications, psql and tools such as pgAdmin or DBeaver connect to the database server here.
- Service
- PostgreSQL
- Protocol
- TCP
- IANA registry
- Officially assigned: postgresql (PostgreSQL Database), TCP/UDP
Check if a port is open on your IP
We only check the address you are visiting from, one TCP port at a time. You cannot enter someone else’s address: this is not a port scanner.
Is it safe to open port 5432?
By default PostgreSQL listens only on localhost (listen_addresses). If you open it to other machines, allow specific addresses in pg_hba.conf with scram-sha-256 passwords and SSL, and keep 5432 closed to the internet at large.
Sources
“Port 5432 is already in use”: how to fix it
The error means another program is already listening on port 5432. Find its process ID (PID), then stop that program or start yours on a different port.
Windows (Command Prompt or PowerShell as administrator)
netstat -ano | findstr :5432taskkill /PID <PID> /FmacOS
lsof -nP -iTCP:5432 -sTCP:LISTENkill <PID>Linux
sudo ss -ltnp | grep :5432sudo lsof -i :5432sudo kill <PID>Replace <PID> with the number from the last column (Windows) or the PID column (macOS, Linux).
Why a port can look closed when your server is running
Most home networks sit behind a router doing NAT: the router owns the public address, and your computer has a private one such as 192.168.1.10. A connection from the internet reaches the router and stops there unless you add a port forwarding rule to your computer.
Many mobile and some home providers go further and use carrier-grade NAT (CGNAT): several customers share one public address, and your router itself gets an address from 100.64.0.0/10. Then no rule on your side can open a port; ask the provider for a public IP or use a tunnel or VPN service.
Even with forwarding in place, the firewall on the computer (Windows Defender Firewall, ufw, firewalld) must allow the port, and the program must listen on all interfaces (0.0.0.0), not only on 127.0.0.1.
UDP cannot be checked this way: a UDP service usually stays silent to packets it does not understand, so “no answer” means nothing. This check uses TCP only.
Frequently asked questions
What is port 5432 used for?
Port 5432 is the default port of PostgreSQL. Applications, psql and tools such as pgAdmin or DBeaver connect to the database server here.
Is port 5432 TCP or UDP?
Port 5432 uses TCP. IANA reserves the number for both TCP and UDP, but in practice only TCP is used.
Is it safe to open port 5432?
By default PostgreSQL listens only on localhost (listen_addresses). If you open it to other machines, allow specific addresses in pg_hba.conf with scram-sha-256 passwords and SSL, and keep 5432 closed to the internet at large.
How do I free port 5432 if it is already in use?
Find the process: on Windows run netstat -ano | findstr :5432 and stop it with taskkill /PID <pid> /F; on macOS or Linux run lsof -i :5432 and stop it with kill <pid>.