PRTG charges per sensor — every ping, SNMP OID, or traffic flow consumes one license unit. A 200-device network easily needs 1,000 sensors, putting you at €3,899 per year before adding a single custom check.
Checkmk Raw Edition is permanently free, open-source, and imposes no per-host limits. The central question isn't features — both tools monitor the same devices — it's whether your team runs Windows or Linux and how much you want to pay at scale.
PRTG wins when your team already administers Windows, needs industrial protocol support (Modbus, OPC UA, MQTT), or wants a polished out-of-box experience with minimal Linux knowledge required.
This guide compares real pricing math, auto-discovery depth, IoT support, distributed monitoring, and community sentiment so you can make the right call for your environment.
Editorial policy: How we review software · How rankings work · Sponsored disclosure
PRTG Network Monitor is built by Paessler AG in Nuremberg, Germany and has been a fixture in Windows-centric IT shops since 2003. It runs natively on Windows Server and models every metric as a sensor — a ping check, an SNMP OID, a NetFlow stream, a WMI counter. That model gives PRTG precise, per-metric billing and enormous flexibility, but it also means license costs grow faster than host counts.
Checkmk was created by Mathias Kettner in Munich, evolved out of the Nagios ecosystem, and is now developed commercially by Checkmk GmbH. Its Raw Edition is fully open-source and free forever with no artificial limits. Where PRTG requires you to manually configure each sensor, Checkmk auto-discovers 80–150 check items per host the moment you run its agent — servers, switches, and cloud resources come fully monitored within minutes.
The core tradeoff: PRTG is a better-polished Windows-native tool with strong IoT and industrial protocol support, but its sensor licensing penalizes scale. Checkmk is a Linux-based, automation-first monitoring platform where the free tier genuinely covers most infrastructure teams — but it demands more Linux comfort and offers limited IoT protocol coverage.
PRTG gives teams a way to evaluate infrastructure monitoring software fit, deployment tradeoffs, and day-to-day operational usability.
Sensor-based pricing, Cloud / On-prem deployment, Windows operating-system support, and a trial path for early validation.
PRTG is usually a better fit when cloud / on-prem, sensor-based, and Windows line up more closely with the environment your team actually needs to support.
Checkmk gives teams a way to evaluate server monitoring software fit, deployment tradeoffs, and day-to-day operational usability.
Host-based pricing, Cloud / On-prem deployment, Windows, Linux operating-system support, and a trial path for early validation.
Checkmk is usually a better fit when cloud / on-prem, host-based, and Windows, Linux line up more closely with the environment your team actually needs to support.
Use the matrix as the fastest way to isolate hard differences in pricing, deployment, platform coverage, and trial access before you go deeper into rollout and workflow questions.
PRTG vs Checkmk is a shortlist-stage decision page meant to help IT buyers move from general research into a clearer vendor choice.
PRTG and Checkmk usually stay on the shortlist for different reasons. Use this page to see where one product fits the current environment more cleanly, where the tradeoffs start to matter, and which differences deserve more pressure-testing before the team treats either option as the default choice.
For most IT teams choosing between these two tools in 2026, the decision is simpler than it looks. If your team runs Windows and you have industrial or IoT devices that speak Modbus, OPC UA, or MQTT — PRTG is the right call. No other tool in this category handles OT protocols as natively, and the GUI-driven experience on Windows is genuinely polished.
For everyone else — especially organizations with more than 100 hosts, Linux-competent admins, and a real interest in keeping licensing costs low — Checkmk Raw Edition is the answer. The auto-discovery depth alone saves dozens of hours in initial setup. The €0 licensing cost at any scale is a genuine structural advantage that compounds over years.
Checkmk is also the better choice for MSPs, cloud-native environments, and Kubernetes-heavy infrastructure. The 2,000+ check plugins and the mature distributed monitoring architecture give it genuine breadth that goes beyond what PRTG's sensor model can efficiently cover.
Short version: PRTG is the better tool for Windows-native, IoT/OT, and NetFlow-dependent environments where you can justify the sensor licensing cost. Checkmk is the better tool for scale, cost efficiency, Linux environments, and cloud monitoring — and for most teams at 100+ hosts, the cost argument alone makes Checkmk the default recommendation.
Before booking demos, answer these against your environment. If most resolve cleanly, you are ready to move forward — a smoother sales process is not the same as a better product fit.
Which product matches the team’s current operating model without requiring unnecessary process change?
Which option offers the cleaner path for rollout, onboarding, and long-term operational ownership?
Where do pricing mechanics, integrations, and platform scope create meaningful differences?
If neither option is a perfect fit, which tradeoff is easier to absorb over the next 12 months?
Checkmk is cheaper for almost every environment larger than 15–20 devices. Checkmk Raw Edition is free forever with no per-host limits. PRTG's lowest paid tier is €1,799/year for 500 sensors — enough for roughly 50 devices with standard monitoring depth. At 200 devices, the cost gap reaches €3,899–€7,899 per year in Checkmk's favor depending on how many sensors per device you configure.
Yes. Checkmk Raw Edition is open-source (GPL-licensed) and permanently free with no per-host limits, no feature paywalls on core monitoring, and no trial expiry. It includes the full monitoring engine, 2,000+ check plugins, distributed monitoring, and the alerting system. Paid tiers (Cloud and Enterprise) add MSP multi-tenancy, SLA reporting, and official support contracts — not the core monitoring engine.
No. PRTG's core server requires Windows Server 2016 or later. Remote probes also run on Windows. If you need on-premises monitoring from a Linux host, PRTG is not an option. PRTG Hosted Monitor (SaaS) removes the requirement to run a Windows server yourself, but the underlying platform is Windows-based and you still pay per sensor.
Checkmk Raw Edition is the fully open-source, free version of Checkmk. It includes the complete monitoring engine, auto-discovery, 2,000+ check plugins for servers, network devices, cloud services, databases, and containers, plus distributed monitoring and alerting. There are no host limits and no feature restrictions on core monitoring compared to paid editions. The paid editions add MSP multi-tenancy, some enterprise reporting features, and official support contracts.
Plan for 10–20 sensors per server (CPU, memory, individual disks, network interfaces, key services), 15–30 sensors per managed switch (interfaces, CPU, memory, fan/temp), and 3–5 sensors per simple device (ping, SNMP availability, uptime). A 200-device environment typically needs 1,000–3,000 sensors. Use PRTG's free 30-day trial with unlimited sensors to count your actual sensor consumption before choosing a tier.
Yes. The Checkmk agent for Windows is a lightweight service that collects CPU, memory, disk, network interface, Windows services, event log, and application-specific metrics. It delivers comparable coverage to PRTG's WMI sensors. Auto-discovery configures all checks automatically after agent installation, without manual configuration per metric.
Yes — this is one of PRTG's genuine differentiators. PRTG includes native sensors for Modbus RTU, Modbus TCP, OPC UA, and MQTT. You can monitor PLCs, energy meters, building management systems, HMIs, and industrial controllers from the same dashboard as your IT infrastructure. Checkmk has no native Modbus or OPC UA support and is not designed for OT/ICS environments.
PRTG is easier for Windows-native teams: the installer runs on Windows Server, the GUI walks you through initial setup, and no Linux knowledge is required. Checkmk requires Linux comfort for installation, but its auto-discovery is dramatically faster once deployed — pushing the agent to hosts and running discovery configures 80–150 checks per host automatically, which saves far more time than PRTG's per-sensor manual configuration at scale.
For most network monitoring use cases, yes. Checkmk covers SNMP v1/v2c/v3, agentless device monitoring, interface stats, bandwidth utilization, and availability checks for routers, switches, and firewalls. Where Checkmk cannot replace PRTG is NetFlow/sFlow traffic analysis (not natively supported) and Modbus/OPC UA/MQTT monitoring for OT devices. If those capabilities aren't needed, Checkmk Raw is a fully capable PRTG replacement.
Checkmk Raw Edition is community-supported. You get access to the Checkmk forum, the official documentation, and the Checkmk Exchange (community plugin repository). There is no vendor support contract available for Raw Edition — that requires the Cloud or Enterprise editions. For organizations that need guaranteed response times or professional onboarding assistance, the community-only support model is a real limitation to factor into your evaluation.
Use the software profiles to go deeper on pricing details, integrations, rollout fit, and editorial review before the team commits to a final vendor path.
Go deeper on product profiles, pricing, category context, and glossary terms before committing to a vendor path.
Return to the category hub when the shortlist still needs broader market context before the final vendor decision.
Check which tools in this category offer free tiers, trials, or community editions.
Open the full product profile for deeper pricing, deployment, review, and shortlist context.
Check commercial fit and pricing mechanics directly before treating the comparison as settled.
Open the full product profile for deeper pricing, deployment, review, and shortlist context.
Check commercial fit and pricing mechanics directly before treating the comparison as settled.
Use glossary terms when the comparison raises category language that still needs a clearer definition.
