How to check open ports on a host

You want to know whether port 443 (or 22, or 25, or whatever) is reachable on a given host from the public internet. The Port Checker does this in one click.

Steps

1. Open the Port Checker.
2. Enter the hostname or IP.
3. Add a comma-separated list of ports — or use one of the presets (web, mail, ssh).
4. Run the check.

The result shows OPEN, CLOSED, or FILTERED for each port. FILTERED usually means a firewall is silently dropping the connection.

This is a placeholder. Full guide coming soon.