WebGazer is an uptime monitoring platform that checks if your website is up as it should be and notifies you if anything goes wrong
Monitoro - Monitor webpages and get fresh data sent to your webhooks.
UptimeRobot - Free Website Uptime Monitoring
Visualping - Visualping is the easiest to use website checker, webpage change monitoring, website change detector and website change alert software of the web. Read more about Visualping.
StatusCake - Website Uptime Monitoring & Alerts – Free Unlimited Downtime Monitoring
SEO PowerSuite - Get all SEO tools in one pack - download free edition of SEO PowerSuite and get top 10 rankings for your site on Google and other search engines!
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.