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Port Checker

Test if TCP ports are open on any IPv4 address, IPv6 address, or hostname. Dual-stack: checks both IPv4 and IPv6 simultaneously. Results reflect the server's network perspective.

About Port Checker

Open ports on a server determine which services are reachable from the internet — but what your local firewall config says is open might not match what's actually accessible externally. This tool checks whether a specific port on any host is open or closed from the perspective of an outside connection, giving you a real-world view rather than a theoretical one.

Supports IPv4, IPv6, and hostnames. When you enter a hostname, both its A (IPv4) and AAAA (IPv6) records are resolved and tested in parallel, giving you full dual-stack visibility in one check. You can also enter a bare IPv6 address directly (e.g. 2001:db8::1 or [2001:db8::1]).

Useful for server administrators, developers deploying applications, and sysadmins doing firewall verification. Check that your web server's ports 80 and 443 are publicly accessible on both IPv4 and IPv6, confirm an SSH port is reachable, or verify that a database port is correctly blocked from external access.

Host (IPv4, IPv6, or hostname)
Port Presets (click to toggle)
Select Ports to Check
Common Services
🟡 Grin Mainnet
🟢 Grin Testnet
Custom Ports (comma-separated, max 5 — e.g. 22,443,8080)
Address Port Service Status
ℹ️ Checks are performed via a server-side TCP probe. Results reflect what the server can reach — not your local network. A closed result may mean the port is firewalled or the service is not running.
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