Open Ports Scanner shows every open TCP and UDP port and network connection on your computer, IPv4 and IPv6, together with the process that owns it — and who is on the other end. For each connection you see the protocol, process ID, process name or full path, local and remote addresses and ports, the connection state, the remote host name and the network that owns the remote address.

It is a fast, readable replacement for netstat. Use it to find unknown programs talking to the Internet, detect trojans and other malicious software, check which services are listening on your machine and troubleshoot network problems. The list updates automatically and without flicker: new connections flash green and closed ones flash red, so you can watch network activity as it happens.

Supported Features

Open ports and connections

• All TCP and UDP endpoints, IPv4 and IPv6, with the owning process ID and process name or full file path.
• Local and remote addresses and ports and the connection state (LISTEN, ESTABLISHED, TIME_WAIT and others).
• Display filter: show or hide TCP v4, UDP v4, TCP v6 and UDP v6 connections.
• Sort by any column with a click; column widths are remembered.
• Choose the columns to display: Protocol, PID, Process Name, Local Address, Local Port, Remote Address, Remote Port, Connection State, Remote Host and AS / Organization.

Real-time monitoring

• Automatic refresh at the interval you choose with a slider; start and stop monitoring at any time.
• Flicker-free updates: only rows that changed are updated, and your selection and scroll position are kept.
• Change highlights: new connections flash green, closed connections flash red.
• Status bar statistics: total endpoints, how many are shown, established and listening, and the refresh interval.
• Run minimized in the system tray, and keep the window always on top.

Find out who your computer is talking to

• Remote Host column with the reverse DNS name of each remote address.
• Optional AS / Organization column with the network that owns the address — for example Google, Microsoft, Amazon, Cloudflare or your ISP.
• IP Info window with the official registration record (RDAP) of the address: network name and range, CIDR, country, registration dates, the organization that holds it and its abuse contact. Copy the record or open it in your browser.
• Private and local addresses are recognized and never looked up; the Remote Host and AS / Organization columns can be turned off in Settings.

Search

• Search bar (Ctrl+F) filters the list as you type, across all visible columns: a process name, a port, an IP address, a host name or a connection state.
• Press Enter or Down to jump to the results; Esc clears the search, a second Esc closes the bar.

Actions

• Close an unwanted TCP connection without terminating the process that owns it.
• Show in Windows Explorer: open the folder that contains the process file.
• Copy the remote address to the clipboard, and view full connection details.
• Export the list to a CSV file for Excel, or print it.
• Elevate: restart with administrator rights to see the names of all processes, including system services.

Main Window

The connection list with the Search bar above it, the Remote Host and AS / Organization columns, and the IP Info window showing the registration record of a remote address. The status bar at the bottom shows the connection statistics.

Open Ports Scanner Help

Start the program and the list of open ports and connections appears immediately. It refreshes automatically; click a column header to sort the list, click it again to reverse the order. Some process names are visible only to administrators: use Action > Elevate Process to restart the program with administrator rights.

These are the most frequently used commands. You can run them from the toolbar:

Refresh	Refresh the list of connections now.
Export	Save the list to a CSV file.
Terminate	Close the selected TCP connection.
Settings	Choose the protocols and columns to display and the refresh speed.
Search	Show or hide the Search bar (Ctrl+F).
About	Show the program version and registration information.

Right-click a connection for more commands: Close Connection, Show in Windows Explorer, Copy Remote Address and IP Info. Double-click a connection to see all its details. Note that Close Connection closes only the TCP connection; the underlying process is not terminated.

IP Info. Right-click a connection and choose IP Info, or use Action > IP Info, to see who owns the remote address: its host name, AS / organization and the full RDAP registration record. Copy copies the record to the clipboard and View RDAP Record opens it in your browser.

Settings. Options > Settings lets you show or hide TCP v4, UDP v4, TCP v6 and UDP v6 connections, show the full file name and path of each process, choose the columns, and turn automatic refresh on or off and set its speed. The Remote Host column uses your DNS server; the AS / Organization column (off by default) sends remote addresses to Team Cymru, a third-party service.

Monitoring. Action > Start Monitoring and Stop Monitoring pause and resume automatic refresh. Options > Always on top keeps the window above other windows. Minimize the program to keep it running in the system tray.

This software is shareware. Please refer to the license agreement for its distribution rights.

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