Screenshot Machine - Screenshot machine is an online website capturing service. Creates a screenshot or thumbnail of any online web page in couple of seconds for free.
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.
URL2PNG - Screenshots as a Service. Capture snapshots of any website, right in your app, quickly and reliably.
StatusCake - Website Uptime Monitoring & Alerts – Free Unlimited Downtime Monitoring
CloudBrowser.co - A supremely flexible and reliable HTTP API that supports professionals and enterprise alike in the...
Better Uptime - We call you when your website goes down