Paessler PRTG costs $35/mo.
These cost $0.
6 free alternatives to Paessler PRTG, checked for license, recent activity and real adoption. Each one tells you the catch, so you can switch with your eyes open.
The top-rated free, open-source replacement for Paessler PRTG is NetData (Open Source Open Source). Across this category, 6 self-hostable tools are available (including NetData and Scanopy). Switching a 5-person team saves up to $2,100/year compared to Paessler PRTG's $35/mo subscription.
The catch: Requires self-hosting setup, updates, and server maintenance compared to managed Paessler PRTG.
Paessler PRTG vs Free Alternatives
Quick side-by-side comparison · $0/mo vs $35/mo
| Alternative | Type | License | Where It Runs | Stars | Head-to-Head |
|---|---|---|---|---|---|
| NetData | open source | Open Source | Self-host | ★ 81.3k | Paessler PRTG vs NetData → |
| Scanopy | open source | Open Source | Self-host | ★ 5.9k | Paessler PRTG vs Scanopy → |
| Zabbix | open source | Open Source | Self-host | ★ 6.5k | Paessler PRTG vs Zabbix → |
| Checkmk | open source | GPL-2.0 | Self-host | ★ 2.6k | Paessler PRTG vs Checkmk → |
| Icinga | open source | Open Source | Self-host | ★ 2.2k | Paessler PRTG vs Icinga → |
| Nagios | open source | Open Source | Self-host | ★ 2.1k | Paessler PRTG vs Nagios → |
The picks
6 open source · ranked by fit
- 01
NetData
open sourceOpen SourceSelf-host81.3knov 2026Powerful, efficient, and user-friendly monitoring solution for servers, containers, and applications with instant insights and alerts.
The catch vs Paessler PRTGRequires self-hosting setup, updates, and server maintenance compared to managed Paessler PRTG.
Install, platforms & data +
- platforms
- webself-hosteddocker to self-host
- install
- Clone https://github.com/netdata/netdata or deploy with Docker Compose
- setup
- Deploy via Docker or binary release from GitHub and configure environment variables.
- your data
- All application data and configuration live on your own server or local database.
- checked
- 2026-11-07
- 02
Scanopy
open sourceOpen SourceSelf-host5.9knov 2026Discovers your network via SNMP, LLDP, and ARP, then builds and maintains L2/L3 topology diagrams, host inventories, and service dependency maps automatically.
The catch vs Paessler PRTGRequires self-hosting setup, updates, and server maintenance compared to managed Paessler PRTG.
Install, platforms & data +
- platforms
- webself-hosteddocker to self-host
- install
- Clone https://github.com/scanopy/scanopy or deploy with Docker Compose
- setup
- Deploy via Docker or binary release from GitHub and configure environment variables.
- your data
- All application data and configuration live on your own server or local database.
- checked
- 2026-11-07
- 03
Zabbix
open sourceOpen SourceSelf-host6.5knov 2026Monitors networks, servers, cloud services, IoT, and OT environments with no per-device licensing fees, available self-hosted or as a managed SaaS platform.
The catch vs Paessler PRTGRequires self-hosting setup, updates, and server maintenance compared to managed Paessler PRTG.
Install, platforms & data +
- platforms
- webself-hosteddocker to self-host
- install
- Clone https://github.com/zabbix/zabbix or deploy with Docker Compose
- setup
- Deploy via Docker or binary release from GitHub and configure environment variables.
- your data
- All application data and configuration live on your own server or local database.
- checked
- 2026-11-07
- 04
Checkmk
open sourceGPL-2.0Self-host2.6knov 2026Monitor your entire IT infrastructure with 2,000+ plugins, automated discovery, and scalable architecture. Open source and enterprise solutions available.
The catch vs Paessler PRTGRequires self-hosting setup, updates, and server maintenance compared to managed Prtg.
Install, platforms & data +
- platforms
- webself-hosteddocker to self-host
- install
- Clone https://github.com/tribe29/checkmk or deploy with Docker Compose
- setup
- Deploy via Docker or binary release from GitHub and configure environment variables.
- your data
- All application data and configuration live on your own server or local database.
- checked
- 2026-11-07
- 05
Icinga
open sourceOpen SourceSelf-host2.2knov 2026Monitor networks, servers, and cloud environments with flexible open-source solution. Custom checks, fast alerts, and complete infrastructure control.
The catch vs Paessler PRTGRequires self-hosting setup, updates, and server maintenance compared to managed Paessler PRTG.
Install, platforms & data +
- platforms
- webself-hosteddocker to self-host
- install
- Clone https://github.com/icinga/icinga2 or deploy with Docker Compose
- setup
- Deploy via Docker or binary release from GitHub and configure environment variables.
- your data
- All application data and configuration live on your own server or local database.
- checked
- 2026-11-07
- 06
Nagios
open sourceOpen SourceSelf-host2.1knov 2026Free open source IT monitoring solution for servers, networks, and applications. Trusted by 1M+ users worldwide with powerful alerting and enterprise-grade features.
The catch vs Paessler PRTGRequires self-hosting setup, updates, and server maintenance compared to managed Paessler PRTG.
Install, platforms & data +
- platforms
- webself-hosteddocker to self-host
- install
- Clone https://github.com/nagiosenterprises/nagioscore or deploy with Docker Compose
- setup
- Deploy via Docker or binary release from GitHub and configure environment variables.
- your data
- All application data and configuration live on your own server or local database.
- checked
- 2026-11-07
Paessler PRTG Head-to-Head Comparisons (2027)
Side-by-side trade-off breakdowns · 6 free alternatives
Frequently Asked Questions
Direct answers · Paessler PRTG open-source replacements
What is the best free alternative to Paessler PRTG?+
The top free alternative to Paessler PRTG is NetData (open source, Open Source). Powerful, efficient, and user-friendly monitoring solution for servers, containers, and applications with instant insights and alerts. Other popular Paessler PRTG replacements include Scanopy, Zabbix, Checkmk.
Can I self-host a free replacement for Paessler PRTG?+
Yes. Of the 6 free alternatives to Paessler PRTG, 6 can be self-hosted on your own server or local machine: NetData (Open Source), Scanopy (Open Source), Zabbix (Open Source), Checkmk (GPL-2.0), Icinga (Open Source), Nagios (Open Source).
How much does switching from Paessler PRTG to a free alternative save?+
Paessler PRTG starts at $35/month per seat ($420/year). Switching a 5-person team to a free alternative like NetData saves $2,100 per year in software subscription fees.
Should I vibe-code or build my own Paessler PRTG clone from scratch?+
Our build verdict for Paessler PRTG is NO (use a free alternative, save the tokens). Instead of paying recurring SaaS fees for Paessler PRTG or rebuilding it from scratch, deploy one of the 6 battle-tested open-source alternatives like NetData.
What is the catch when switching from Paessler PRTG to NetData?+
Requires self-hosting setup, updates, and server maintenance compared to managed Paessler PRTG.
