Tenable.io - Tenable.io Cyber Exposure platform helps to protect any asset on any computing platform and eliminate blind spots.
IP-Toolbox.com - IP-Toolbox.com is the best site for quick and easy viewing of your public IP address and other related information.
BreachLock - BreachLock is a versatile platform that provides scalable and smooth penetration testing services for vulnerabilities.
GRC Port Scan - GRC Internet Security Port Scanner. Tests for open ports on your external IP address.
Qualys - Qualys helps your business automate the full spectrum of auditing, compliance and protection of your IT systems and web applications.
TrueIP - TrueIP is a small program that runs in the system tray, monitoring your IP address(es).