1. With website monitoring from Pingdom you will be the first to know when your website is down. No installation required. 30-day free trial.

  2. Free Website Uptime Monitoring

  3. StatusCake | Website Uptime Monitoring & Alerts – Free Unlimited Downtime Monitoring

  4. Site24x7 offers both free & paid website monitoring services. Monitor websites remotely and receive instant email/sms alerts if your website becomes unavailable. View uptime & performance graphs of your website monitors.

  5. RapidSpike is an uptime and performance monitoring service for websites and web applications.

  6. Uptime & performance monitoring for websites and APIs.

  7. Pingometer is a service that monitors the uptime, downtime, and performance of websites. Get 24/7 monitoring - sign up for your FREE account today!

  8. Port Monitor is an easy tool that does website and server monitoring 24/7 every 60 seconds for free. It records uptime, performance and downtime causes

  9. updown.io is a HTTP(S)/TCP/ICMP monitoring service which checks periodically the URL you want and reports back any anomaly.

  10. Downtime Monkey: website downtime alerts & uptime monitoring worldwide.

  11. Monitis specializes in IT monitoring, covering server, website, app monitoring and more within an all-in-one monitoring platform.

  12. AlertBot provides availability and performance monitoring from an end user perspective.