Pingdom - With website monitoring from Pingdom you will be the first to know when your website is down. No installation required. 30-day free trial.
Web Load Speed Test - Test your website load speed from 6 locations at once
StatusCake - Website Uptime Monitoring & Alerts – Free Unlimited Downtime Monitoring
Smaller - Make your websites load faster
Better Uptime - We call you when your website goes down
speedtest-cli - Test your download speed using SpeedTest on the command-line