Network Tools

Port Checker

Check if TCP ports are open on any host or IP. Test up to 10 ports at once and see response latency — useful for firewall and server debugging.

TCP
Up to 10 Ports
Latency
Open / Closed Status
Instant

Host

Ports

Comma-separated, up to 10

Enter host and ports to check

Port checker

Test whether a TCP service accepts connections on a hostname or IP address. Use comma-separated ports for common services such as HTTP, HTTPS, SSH, and databases.

Interpretation

An open result means a connection was accepted from the checker. Closed or filtered results can also reflect firewalls, routing, or service configuration.

Frequently Asked Questions

What does a port checker do?: A port checker attempts a TCP connection to a specific port on a host. If the connection succeeds, the port is open; if it is refused or times out, the port is closed or filtered.
What is a port number?: Port numbers (0–65535) identify specific services on a network host. Common ports: 80 (HTTP), 443 (HTTPS), 22 (SSH), 3306 (MySQL), 5432 (PostgreSQL).
Why might a port appear closed when it is open?: Firewalls, NAT, security groups, or load balancers may block external connections. The port may be open internally but closed to external traffic.
Can I check multiple ports at once?: Yes. Enter a comma-separated list of ports (e.g. 80,443,22) to check them all in one request.

Disclaimer

This tool is provided for general informational and utility purposes only. Results may be inaccurate, incomplete, outdated, or contain errors. Always verify results before relying on or using them.

Some tools may use AI, automated processing, third-party services, or server-side processing. Do not rely on these tools as a substitute for professional advice.

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Port checker

Test whether a TCP service accepts connections on a hostname or IP address. Use comma-separated ports for common services such as HTTP, HTTPS, SSH, and databases.

Interpretation

An open result means a connection was accepted from the checker. Closed or filtered results can also reflect firewalls, routing, or service configuration.

Frequently Asked Questions

What does a port checker do?

A port checker attempts a TCP connection to a specific port on a host. If the connection succeeds, the port is open; if it is refused or times out, the port is closed or filtered.

What is a port number?

Port numbers (0–65535) identify specific services on a network host. Common ports: 80 (HTTP), 443 (HTTPS), 22 (SSH), 3306 (MySQL), 5432 (PostgreSQL).

Why might a port appear closed when it is open?

Firewalls, NAT, security groups, or load balancers may block external connections. The port may be open internally but closed to external traffic.

Can I check multiple ports at once?

Yes. Enter a comma-separated list of ports (e.g. 80,443,22) to check them all in one request.

Disclaimer

Some tools may use AI, automated processing, third-party services, or server-side processing. Do not rely on these tools as a substitute for professional advice.