Sites and apps similar to Port Checker include PortKiller, which is free and open source. Other options are Port Checker App, CurrPorts and PortsMonitor. In total there are four Network Monitors like Port Checker for Mac and Windows.
Advanced multi-OS desktop tool for monitoring and managing local TCP ports, identifying bound processes, watching ports for notifications, handling Cloudflare Tunnels, filtering and pinning, managing Kubernetes port-forwards with logs, plus real-time process termination.
PortChecker.app is a free online utility that instantly checks open ports on your device and server. The tool supports remote port scanning, IP lookup, and network diagnostics, making it a reliable solution for developers, system administrators, and cybersecurity professionals.
Displays all open TCP/IP and UDP ports with full process details including name, path, version, creation time, and user information. Supports closing connections, killing processes, marking suspicious ports, exporting data in multiple formats, and portable operation for network monitoring.
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PortsMonitor is a system utility for monitoring system TCP/IP network connections by application, and connections' status. With Search Expression support, you can filter connection with preferred conditions.
