Overview

Checkmk monitors cloud, hybrid and data-center infrastructure, including servers, networks and containers. For server monitoring, it offers more than 2,000 smart checks, automatic discovery and network mapping across web, mail and database servers. That breadth gives teams several ways to cover mixed environments rather than tying monitoring to one operating system or collection method.

Teams can deploy it on customer hardware or in virtualized environments, using packages for major Linux distributions, Docker or a Virtual Appliance. A single instance can monitor thousands of servers, with distributed monitoring available for horizontal scaling. This makes Checkmk viable beyond a single site, while its free Community plan is intended for small infrastructures and scales to approximately 100 hosts.

Key features

Multiple monitoring methods: Native agents support Windows, Linux and other operating systems; agentless SNMP and TCP/UDP checks cover systems where installing an agent is unsuitable. API-based checks can use HTTP/XML, SSH or TELNET, giving teams flexibility across different infrastructure types.
Cloud monitoring: AWS, Azure and Google Cloud Platform coverage includes automatic detection of cloud components and Quick Setup. This is useful for teams managing cloud alongside on-premises systems, though the product’s value depends on needing that breadth.
Integrations and automation: Community includes more than 2,000 built-in integrations, with REST APIs and custom automation scripts also supported. That provides a substantial starting point for connecting monitoring to existing workflows.
Security and support: Ultimate offers zero-inbound, fully encrypted monitoring using push agents and Checkmk Relay. The Trust Center carries ISO 27001:2022, SOC 2 Type I, GDPR, SIG, EU AI Act and DORA badges. Pro support runs 8h x 5d; Ultimate provides 10h x 5d, with an option to upgrade to 24h x 5d.

Pricing

Checkmk uses a freemium model, with a free plan, paid options from €190/mo (annual), and a 30-day trial. The plan figures below are presented separately in USD, so compare the stated prices and billing terms as shown.

Community: 0.00 USD per free, billed forever free of charge. It includes more than 2,000 pre-built integrations and community support, with a scope of up to approximately 100 hosts. This is the sensible starting point for small infrastructures; the host limit and community-only support make it less suited to larger or support-dependent operations.
Synthetic Monitoring: 0.00 USD per month, billed annually, at $0.00/test with 3 free tests. It is available with Pro and Ultimate, so it is an included limited allowance rather than a standalone alternative to those plans.
Pro: 275.00 USD per month, billed annually, from $275/month. It is described as as low as ~$2.75/host per month, equivalent to ~3,000 services, and includes 8h x 5d professional support. This fits organizations that need paid capacity and weekday support without Ultimate’s stated support tier.
Cloud: 290.00 USD per month with monthly billing, at ~$8.70/host per month. It covers 1K–50K services, with one host equivalent to ~30 services and 99.5% availability. Its monthly billing and service range suit cloud-monitoring needs where those capacity and availability terms fit.
Ultimate: 400.00 USD per month, billed annually, from $400/month. It is described as as low as ~$4.00/host per month, equivalent to ~3,000 services, and includes 10h x 5d professional support, upgradeable to 24h x 5d. The higher price is aimed at teams that need its encrypted push architecture or stronger support coverage.

Platforms

Checkmk supports API, Linux, macOS, self-hosted, web and Windows. Its hybrid deployment model and multiple-OS coverage make it suitable for teams monitoring a mix of hosted and customer-managed systems.

Who it's for

Checkmk is a strong choice for infrastructure teams responsible for varied server, network and cloud environments, especially when agentless or API-based checks matter alongside native agents. Its scaling and deployment options also suit organizations that expect to grow beyond one monitoring instance. Small teams can start with Community, but should look at paid plans when the approximately 100-host scope or community support is no longer enough.

Pros and cons

Pro — Broad monitoring coverage: Agents, SNMP, TCP/UDP and API-based checks give teams options across heterogeneous infrastructure.
Pro — Room to scale: One instance can monitor thousands of servers, and distributed monitoring enables horizontal scaling.
Pro — Generous free starting scope: Community includes more than 2,000 integrations and is free forever, making it practical for smaller environments.
Con — Community has a clear ceiling: Its approximately 100-host scope and community support will not suit larger deployments or teams that need professional support.
Con — Paid costs and capacity are plan-specific: Pro and Ultimate have annual billing and stated service equivalents, while Cloud uses monthly billing and a different service range. Buyers should match the plan’s capacity and terms to their monitoring workload.

Alternatives

For service-provider-oriented browsing, see Managed Service Provider Software; for category comparisons, also see Cloud Monitoring, Infrastructure Monitoring, Metrics Monitoring Tools, Network Performance Monitoring Software and Hardware Monitoring Software.

Breeze is worth considering if unlimited devices, all 64 modules and a self-hosted free Community plan matter more than Checkmk’s stated infrastructure-monitoring focus.
ManageEngine MSP Central may fit buyers seeking a paid, device-based network monitoring and management plan at 1.00 USD per month per device.
Atera is another paid option with a free trial and an unlimited-endpoints Pro plan.
ManageEngine Endpoint Central may suit endpoint-management needs; it has a free edition for 25 endpoints and a Professional on-premises annual option at 795.00 USD per year for 50 endpoints and one technician.
Tactical RMM offers a free plan and a self-hosted Tier 1 Starter plan at 55.00 USD per month for 0 to 199 endpoints, with a 48-hour support SLA.
Site24x7 MSP is a paid, trial-available alternative.
Datto Endpoint Backup for Windows is a paid alternative with consumption-based pricing for storage used.
Liongard is a paid alternative with monthly, per-user pricing and 105+ integrations included in LiongardIQ.

Verdict

Choose Checkmk if you need broad infrastructure monitoring that can span servers, networks and cloud services, with multiple collection methods and a path from a free small-environment plan to distributed scale. Look elsewhere if your environment exceeds Community’s approximately 100-host scope but cannot justify paid capacity, or if you need a different specialization such as endpoint management or backup.

	Checkmk	Observatorium
Free plan	Yes	No
Free trial	Yes	No
Paid from	$275/mo	—
Open source	No	No
Platforms	api, Linux, macOS, self-hosted, Web, Windows	self-hosted
Free plan	Yes	—
Kubernetes logs	—	Yes
Distributed tracing	—	No
Managed Kubernetes support	—	Yes

Checkmk vs Observatorium

Checkmk

Observatorium