Open Source Server Monitoring Software (2026)

Open Source
Get Started with a 30-day free trial. No Credit Card required. Pricing options are available in Yearly, Monthly and Hourly models. STARTER Best suited for small teams. $9/mo PRO Best suited for medium sized teams. $35/mo ENTERPRISE Best suited for enterprises. $225/mo

Open Source
Pricing plans: Hobbyist (free): monitor up to 20 jobs. Business ($20/mo): monitor up to 100 jobs. Business Plus ($80/mo): monitor up to 1000 jobs.

Open Source
Sign up for free access with our perpetual free tier and 100 GB/month of data ingest included.

Open Source
Zabbix Cloud is offered across seven pricing plans, starting at $50/month. A 30 free trial is also available. Please contact Zabbix for detaild pricing information.

Open Source
Oh Dear's pricing is transparent: you simply pay for the amount of websites you want to monitor. All of our plans - the smallest and the biggest - have access to all features and settings. We don't hide any security toggles behind an Enterprise plan. Every user has access to every feature.

Open Source
Icinga Monitoring is open source and free to use. Annual subscriptions are available for official Icinga support plans and certain operating system specific packages (AL, RHEL, SLES). Contact Icinga for pricing details.

Open Source
Wireshark is available to users for free.

Open Source

Open Source
Nagios XI's plans are primarily based on the Node-count of the license. A Node is anything with an IP address or Fully Qualified Domain Name (FQDN) that you would like to monitor (switches, routers, firewalls, workstations, and other network devices). There are no restrictions on the number of Services you can monitor. While paid licenses of Nagios XI do not contain any software-imposed limitations, we have found that systems performing more than 15,000-20,000 checks in a 5-minute interval should consider following our Server Considerations Guide to ensure the best performance on your installation. Nagios XI also offers an Enterprise add-on which enhances the software's capabilities. This addition allows users to schedule reports, project future values with capacity planning, and much more. Refer to our Enterprise documentation or contact a Nagios sales representative to learn more about the capabilities of the Enterprise-level license. With the purchase of a Nagios XI license, you receive access to Premium Features as part of your Maintenance & Support benefits for the first year. After the first year, renewal of your Maintenance & Support plan is required to maintain this feature set. This includes features such as Single-Sign On (SSO) via MS Azure AD, the Nagios Mod-Gearman user interface, and a collection of premium wizards! To learn more and see the full list of features, you can visit our article on Premium Features or contact Nagios sales.

Open Source
Choose between five Editions aimed at monitoring any kind of cloud and IT infrastructure. Fine-tune your investment to your scale and support requirements. IT monitoring has never been more flexible.

Open Source
Contact Chef for pricing information.

Open Source
We offer everything from small plans for individual developers to gargantuan plans for Fortune 500 companies sending millions of metrics every month. If you're currently running Graphite at scale, we can help - we collect millions of metrics and billions of datapoints a day.

Open Source
Please contact Opmantek directly for pricing information.

Open Source
A 30-day free trial is offered for HashiCorp Consul Enterprise plan. Please contact HashiCorp directly for pricing details.