inSSIDer Alternatives

NetSpot is a free app for wireless site surveys, Wi-Fi analysis, and troubleshooting

Wifi Analyzer is a handy tool which helps you to select a better channel for your wireless router.

Vistumbler is a wireless network scanner for Windows Vista and Windows 7. Features:

WiFi Explorer is a tool to scan, find, and troubleshoot wireless networks.

Kismet is an 802.11 layer2 wireless network detector, sniffer, and intrusion detection system.

Official source of information about Netstumbler.

Acrylic WiFi is a free to use WiFi scanning and channel scanning tool for the Windows operating devices only.

With Homedale you can search for Wi-Fi / WLAN Access Points and monitor their signal strength.

A 802.11 wireless scanner and connection manager for Mac OS X.

NetSurveyor is an all one network diagnosing and troubleshooting tool for the Windows operating systems.

Wireshark is a network protocol analyzer for Unix and Windows. It lets you capture and interactively browse the traffic running on a computer network.

WiFi Analyzer. See your WiFi signal on a visually comprehensive map and make sure you are getting the best of your network

Scans wireless networks in your area and displays extensive information, including: SSID, MAC Address, PHY Type (802.11g or 802.11n), RSSI, Signal Quality, Frequency, Channel Number, and more...