Port 8443: HTTPS alternate
Common alternative port for HTTPS.
- Port
- 8443
- Protocol
- TCP
- Service
- HTTPS alternate
- Exposure
- Expose only with access controls
What is port 8443 used for?
Admin consoles and apps that cannot use 443.
Is it safe to expose port 8443 to the internet?
Treat it like port 443; restrict admin interfaces.
If port 8443 seems closed or unreachable
- Check that the HTTPS alternate service is running and listening on port 8443, not only on 127.0.0.1.
- Check the firewall on the host itself (Windows Defender Firewall, iptables, nftables, ufw) for a rule that allows TCP 8443.
- If the host is behind a router, confirm the forwarding rule points to the correct internal address and that your internet provider does not use carrier-grade NAT.
- Test from outside your own network. A port can be open locally and blocked at the edge, or the other way round.
Using port 8443 safely
Port 8443 can be exposed when the host exists to provide this service, but add controls: restrict source addresses where you can, require strong authentication and encryption, and monitor the logs for repeated failures.
Check whether port 8443 is open on your host
The check connects from our server, so it shows what the internet can reach.
Open the port checker