Nmap

Network discovery and security auditing tool. Port scanning, OS detection, and vulnerability discovery.

About Nmap

Nmap (Network Mapper) is a free and open source utility for network discovery and security auditing. It uses raw IP packets to determine available hosts, services, operating systems, packet filters, and dozens of other characteristics.

Key Features

Port scanning & service detection
OS fingerprinting
NSE scripting engine
Traceroute & host discovery
Output in XML, grepable, normal
Zenmap GUI available

Why choose Nmap?

Nmap is an open source alternative to Masscan, Angry IP Scanner. Licensed under NPSL, it gives you full access to the source code and the freedom to modify, self-host, and contribute. It is available as a desktop or web application.