This is a list of free Cybersecurity Tools:
DownDetector > See what internet service providers are down.
Have I Been Pwned > Is your email on the dark web?
IOT Scanner > Are your IOT devices on your network secure?
Krack Detector > Is your network vulnerable to the Krack Attack?
ROBOT Attack > ROBOT attack information and test tool
SSL BlackList > Full list of bad SSL certificates
SSL Server Tester > Is your SSL/TLS Server correctly configured?
Threat Crowd > A Search Engine for threats
Virus Total > Upload any suspicious file to check if its infected
Web Site Reputation Lookup > Is a web site legitimate?