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TCP Network Port Test

Online Port Checker

Check whether a specific TCP port is open or closed on a public domain or IP address. Quickly test common web, email, database and server ports from your browser.

TCP Port Check
IPv4 & IPv6
Fast Results
Public Hosts Only
TCP Connection Visual ● Ready
PORT 443 OPEN SERVICE HTTPS PROTOCOL TCP STATUS OPEN

Check a TCP Port

Enter a public hostname or IP address and one TCP port number to test whether the port accepts a connection.

Port Checker Public TCP port availability test
This public checker tests one TCP port at a time. Private, loopback and reserved network destinations are blocked.
Common TCP Ports
Checking TCP connection...
Testing the selected public host and port.
Port Open
Port 443 is open
The target accepted a TCP connection.
Target —
Resolved IP —
Port / Service —
Response Time —

What Is a Port Checker?

A Port Checker tests whether a specific TCP port on a public server accepts a network connection. Ports are numbered endpoints used by applications and network services.

For example, web servers commonly use TCP port 80 for HTTP and port 443 for HTTPS. SSH commonly uses port 22, while mail and database services use other dedicated ports.

What Does “Open Port” Mean?

An open TCP port means that the destination accepted a connection on that port at the time of the test. This usually indicates that a service is listening there.

What Does “Closed” Mean?

A closed or unreachable result means the TCP connection was not accepted. The service may be stopped, the port may be blocked by a firewall, or the server may not allow connections from the checker.

●   ●   ●
$ port-check example.com 443

Resolving host...
IP: 203.0.113.10
Protocol: TCP
Port: 443 / HTTPS
Status: OPEN

✓ TCP connection accepted

What Can a Port Checker Help With?

Use a TCP port check while troubleshooting public-facing servers and network services.

Website Ports

Check common HTTP and HTTPS ports such as TCP 80 and 443 for public web servers.

SSH Services

Check whether a public server accepts TCP connections on the configured SSH port.

Mail Servers

Test common public SMTP, IMAP and POP3 TCP ports when reviewing mail server connectivity.

Database Connectivity

Check whether a deliberately public database endpoint accepts connections on its configured TCP port.

Cloud Servers

Test public service ports while troubleshooting VPS, cloud hosting or server firewall settings.

Troubleshooting

Confirm whether a public service appears reachable before checking application-specific configuration.

How to Use the Port Checker

Check one public TCP port in three simple steps.

1

Enter a Host

Type a public domain name or public IPv4/IPv6 address.

2

Enter a Port

Choose a TCP port between 1 and 65535, such as 80, 443 or 22.

3

Check the Result

See whether the TCP connection was accepted and review the resolved IP, service and response time.

Port Checker FAQs

Common questions about TCP ports and port availability.

A TCP port is a numbered network endpoint used by an application or service. Common examples include port 80 for HTTP and port 443 for HTTPS.
An open result means the public destination accepted a TCP connection on the selected port at the time the test was performed.
The service may not be running, the server may reject the connection, or a firewall may be filtering access to that TCP port.
Yes. Port 80 is commonly used for HTTP and port 443 for HTTPS. Select one port at a time and run the check.
No. This public tool intentionally checks only one user-selected TCP port at a time.
Private, loopback and reserved network ranges are blocked so the public checker cannot be used to reach internal network resources from the web server.
Yes. Public IPv6 addresses are supported when your hosting server has IPv6 connectivity.
Yes. The Port Checker can be used online without registration to test a single public TCP port.