If your server goes down, you want to know immediately. Here are 15 of the best Uptime Monitoring Services for your server.

Among the many factors to consider before you buy a VPS is uptime. It is very important to consider when you want to use that VPS to host your high-traffic websites. Downtime is not good and negatively impacts your site’s SEO. Therefore, it is better to know faster when your sites go down.

Here is the list of online services that offer free uptime monitoring. These services alert you either via email or SMS or any other modern means of contact that immediately alerts you of a downtime.

1. Pingdom: It is not just a web app providing uptime monitoring service but also provides other useful tools like website speed test, ping, DNS health checker and traceroute. The cheapest plan or their premium plans is available for $6.96 which allows you to have 10 checks plus 20 SMS alerts per month. Also, there exists a free plan that lets you monitor one website/server and includes Real User Monitoring.
2. Site 24×7: It offers free uptime monitoring services with website, server, network, port, and FTP monitoring and testing SSL certificate expiry. Here you can monitor five basic websites from one location. The monitoring is done every 10 minutes as per the free plan. You can always upgrade to paid plans for advanced features.
3. SiteUptime: Using this uptime monitoring service, you can monitor one site for free with SiteUptime. The monitoring interval for the free account is 30 to 60 mins. But in the free plan, you can only receive email alerts. You can refer to their paid plans for more advanced options.
4. Uptime Robot: This one is also my favorite. First, because it is free and secondly, because you can have 50 checks and each checked every 5 minutes, the shortest interval ever available for free service. And, they provide API also.
5. Basic State: Be first to find out about network outages, server overload, server outages, or DNS configuration problems. Using their service, you can check your websites every 15 minutes, get trouble alerts by email, and daily uptime report with 14-day history.
6. Monastic: You will get email alerts when your site goes down and when your site goes up with Montastic uptime monitoring service. It monitors your website’s uptime every 30 minutes under the free plan. And if you want them to monitor your website’s uptime every five minutes and monitor more than three websites, go for their paid plans.
7. Monitor.us: It carries out free uptime monitoring that is easily customizable and has a list of interesting and useful features. Monitor.us not only helps you monitor your site’s uptime but also monitor your network and server performance and page load time. This tool will send you alerts via SMS and emails and to your Android and iOS devices with its mobile monitoring service.
8. Binary Canary: Under the free plan, you get five monitors for free with Binary Canary uptime monitoring services. You can have multiple users per account email, email alerts, or SMS. If you like this service you can access more features by opting for their paid plans.
9. Free Site Status: They monitor your websites and servers from a network of 16 worldwide monitoring stations. To avoid false alarms, they employ advanced verification technology. Free Site Status’s monitoring interval for the free plan is 60 minutes.
10. Internetseer: It features false alarm protection. Also, you also receive a real-time error and recovery notifications and weekly performance reports. The free plan of Internet seer gets 60 minutes monitoring interval.
11. Up panel: It is a free uptime monitoring service that alerts you via email, SMS, or phone if your site is down. Also, you are notified when the site is back online. Up panel, service is absolutely free.
12. Auturis: You can monitor up to five infrastructure resources under the free account of Auris. The monitoring is at an interval of one minute. Also, you will receive unlimited email alerts. Auris have premium plans for small, large, and medium-sized businesses too.
13. Downnotifer: You can monitor your site and get email or SMS alerts using Downnotifer. Signing up with this uptime monitoring service is easy with social login. You will receive extended monitoring reports on your site. If you want to have the premium plan for advanced features, it is available for $14.95 per year.
14. 100 Pulse: It offers two website monitoring for free with a minimum interval of 15 minutes.
15. Uptime Dog: Their free website monitoring service is here right for you. It will check the availability of your website every 2 minutes to see if it is working, and notifies you to your email address if it is down.
16. (new) happyapps.io: An additional uptime monitoring service we came across was happyapps.io. Happy Apps provides a very easy-to-understand UI to monitor your apps. You can get SMS and email messages when any of your apps experience downtime and are the only service to offer App Grouping Hierarchy with system dependency and impact.
17. (new) SuperMonitoring.com: True to their name, SuperMonitoring offers a lot of great options including site checks every 60 seconds, unauthorized changes to files, and form testing, just to name a few.  What’s great is that they also offer a plugin for sites on WordPress or Joomla! platforms, which makes the installation very simple. You can try their service for free but there is a small monthly cost depending on the number of sites you are monitoring.

So, which uptime monitoring service do you use? Or maybe you have another service in mind? Please share with us.