Common usage patterns

Typical ways visitors use this tool.

  • Check whether port 443 is reachable before debugging an HTTPS or reverse-proxy issue.
  • Test SSH, mail, or custom service ports when firewall, NAT, or security-group changes may be blocking traffic.
  • Confirm that a hostname and port combination is open from the public side before escalating a connectivity problem.

Tool overview

A quick summary of what this tool does on the page.

Check open ports online with this free Port Checker. Enter a hostname and port number, run the test, and see whether the service is reachable from the network.

Questions answered on-page

Quick answers to common questions about using this page.

What does Port Checker do?

Port Checker tests whether a target host and port combination appears reachable so you can quickly verify basic service availability.

When should I use Port Checker?

Use it when debugging connectivity, validating firewall changes, checking public service reachability, or confirming that a port is open as expected.

Can Port Checker help with HTTPS or mail ports?

Yes. It is useful for common ports such as 80, 443, 25, 587, 22, and custom service ports when you need a quick network-level check.

Related tools

Open the next tool in the workflow or compare similar options.

Guides and comparisons

Read supporting pages that explain the workflow, common decisions, and related usage patterns.