Check if a specific port is open or closed on any host or IP address. Test TCP connectivity for common service ports like HTTP, SSH, MySQL, and more. Designed specifically for developers and professionals, this free online networking runs entirely in your browser to process tasks quickly and securely. Enjoy unlimited usage with no data tracking, no registration required, and an entirely ad-free experience.
Check if a specific port is open or closed on any host or IP address. This tool performs a server-side TCP connection test to determine port availability, useful for network troubleshooting and security auditing.
Port checks are performed server-side from an independent location. Only basic TCP connectivity is tested — no data is sent to or read from the target service.
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