Port Checker
Check whether a TCP port is open and accepting connections from the public internet.
What is Port Checker?
Network services listen on TCP ports — web servers on 80/443, SSH on 22, databases on 3306/5432. If a port is closed or firewalled, no connection succeeds. This tool tries to open a TCP socket from our server to your host on the specified port — useful for debugging firewall rules, validating that a service is actually exposed, or auditing security.
Frequently asked questions
Why does my localhost service not show as open?▼
We check from the public internet. localhost or RFC 1918 private addresses can't be reached from our server.
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