Wireless Network Watcher for Windows

Wireless Network Watcher 2.45 is a small free utility for Windows by Nir Sofer (NirSoft). You download Wireless Network Watcher to find out which computers and gadgets are connected to your Wi-Fi or wired network right now, and to spot a device that should not be there.

Quick facts

• Version: 2.45
• Developer: Nir Sofer
• System: Windows
• Installation: not required, runs as a single program
• Licence: freeware
• Size: about 524.66 KB according to catalogue data
• Website: nirsoft.net

What it shows

The program scans the network your PC is connected to and builds a table of every responding device. For each one you see the IP address, the MAC address, the company that made the network adapter, and the device name if it can be resolved. It also records when a device was first and last detected, so after a few days you have a simple history of who has been connected. You can leave it running in the background: it rescans at a set interval and can play a sound or show a tray notification when a new device appears. That is handy if you want to know when a neighbour or an unknown gadget joins your Wi-Fi. The results can be exported to text, HTML, CSV or XML for a report. Unlike NetCut and similar tools, Wireless Network Watcher only observes; it does not block or disconnect anything, which makes it safe to use as a pure monitoring tool.

How to use it

1. Download the ZIP archive from the official NirSoft page and unpack it to any folder.
2. Run WNetWatcher.exe; no installation is needed.
3. Wait for the first scan to finish and review the list.
4. Enable background scanning and a beep on new devices in the Options menu if you want alerts.

Requirements

Any Windows PC connected to the network you want to check. It works on Wi-Fi and wired Ethernet networks alike, despite the name. Scanning large corporate networks may require choosing a specific adapter and IP range in advanced options.

What to do if you find a stranger

Check the unknown MAC address against devices in your home, including TVs, speakers and smart plugs. If it is really foreign, change the Wi-Fi password in the router, switch to WPA2 or WPA3 security and disable WPS.

Safety and price

The tool is free. Some antivirus products flag NirSoft utilities as potentially unwanted simply because they reveal network or system information; download only from nirsoft.net to be sure you get the original.

Pros and cons

• Pro: tiny and portable.
• Pro: alerts about new devices.
• Pro: exports to several formats.
• Con: only lists devices, cannot block them.
• Con: device names are not always detected.
• Con: may trigger antivirus warnings.

Alternatives

NetCut on our site can also block devices on your own network, Wireshark analyses traffic in depth, and WinMTR helps diagnose connection problems.