Port 8080 (HTTP alternate)
Port 8080 is registered with IANA as HTTP Alternate. It is the default of Apache Tomcat and Jenkins, a common choice for HTTP proxies, and the usual port for running a second web server without root rights.
- Service
- HTTP alternate
- Protocol
- TCP
- IANA registry
- Officially assigned: http-alt (HTTP Alternate (see port 80)), TCP/UDP
- Commonly used by
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 8080?
Admin panels on 8080 (Tomcat manager, Jenkins, router interfaces) are a frequent target. Do not leave them reachable from the internet without a login, and serve anything public over HTTPS.
“Port 8080 is already in use”: how to fix it
The error means another program is already listening on port 8080. 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 :8080taskkill /PID <PID> /FmacOS
lsof -nP -iTCP:8080 -sTCP:LISTENkill <PID>Linux
sudo ss -ltnp | grep :8080sudo lsof -i :8080sudo kill <PID>Replace <PID> with the number from the last column (Windows) or the PID column (macOS, Linux).
Port 8080 vs 8000
Neither is special in itself: both are high ports any user may open. 8080 is registered as HTTP Alternate and is the default for Tomcat and Jenkins; 8000 is what Django and Python’s http.server pick. Choose either for local development; in production, put the app behind a web server on 443.
Port 8000 (Django, Python)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 8080 used for?
Port 8080 is registered with IANA as HTTP Alternate. It is the default of Apache Tomcat and Jenkins, a common choice for HTTP proxies, and the usual port for running a second web server without root rights.
Is port 8080 TCP or UDP?
Port 8080 uses TCP. IANA reserves the number for both TCP and UDP, but in practice only TCP is used.
Is it safe to open port 8080?
Admin panels on 8080 (Tomcat manager, Jenkins, router interfaces) are a frequent target. Do not leave them reachable from the internet without a login, and serve anything public over HTTPS.
How do I free port 8080 if it is already in use?
Find the process: on Windows run netstat -ano | findstr :8080 and stop it with taskkill /PID <pid> /F; on macOS or Linux run lsof -i :8080 and stop it with kill <pid>.