Top Alternatives to PHP Server Monitor

Port Monitor is an easy tool that does website and server monitoring 24/7 every 60 seconds for free.

Zabbix is enterprise open source monitoring software for networks and applications.

AppBeat is reliable website monitoring service that alerts you when there is a downtime or failure. It also measures performance and provides functional tests.

Nagios known as Nagios Core, is a free and open source computer-software application that monitors systems, networks and infrastructure.

UptimeRobot is a free website uptime monitoring service.

Pingdom helps you give your customers the best possible web experience by offering a Powerful Web Performance Monitoring Solution.

StatusCake delivers accurate global website monitoring for tens of thousands of customers.

Monitis is a web performance monitoring platform.

Pingoscope is a website monitoring site.

Site Down is a site downtime monitoring platform.