Port Checker UDP TCP

Check if TCP or UDP ports are open on any host with our instant online port scanner tool.

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About This Tool

This Port Checker tool allows you to test whether specific TCP or UDP ports are open on any host (domain or IP address). Simply enter the host address, port number, select the protocol (TCP or UDP), and click 'Check Port'. The tool will attempt to establish a connection and report whether the port is open, closed, or filtered. It's useful for network administrators, developers, and IT professionals to verify port accessibility and troubleshoot connectivity issues.

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How to Use

Enter the host (domain name or IP address) in the 'Host' field.
Enter the port number (1-
in the 'Port' field.
Select the protocol (TCP or UDP) from the dropdown.
Click the 'Check Port' button to initiate the scan.
View the results showing port status (open, closed, filtered) and response time.

Frequently Asked Questions

Find Quick Answers

What is the difference between TCP and UDP port checking?

TCP (Transmission Control Protocol) is connection-oriented and requires a handshake, making it more reliable for checking if a service is listening. UDP (User Datagram Protocol) is connectionless and may not always provide definitive results, as some firewalls may drop packets without response.

Why does the tool show 'Filtered' for some ports?

A 'Filtered' status typically means a firewall or network device is blocking the connection attempt, preventing a clear open/closed response. This is common for security-hardened systems.

Can I check multiple ports at once?

This tool currently checks one port at a time for accuracy and simplicity. For multiple port scanning, you would need to run separate checks for each port.

Is this tool safe to use?

Yes, this tool only attempts to connect to specified ports and does not perform any malicious activities. However, always ensure you have permission to scan the target host to avoid legal issues.

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