Best Network Monitoring Software · 2026
Datadog vs 
Nagios XI Datadog vs Nagios XI: on our data-weighted scoring, Datadog edges ahead (8.4 vs 8.0/10). Datadog starts at $5/host/mo and is best for cloud-native teams wanting unified network, infrastructure, and application observability as saas; Nagios XI starts at $2595/one-time (100 nodes, Standard) and is best for teams wanting on-prem, perpetually-licensed infrastructure monitoring with a free open-source core. Choose Datadog for the stronger overall track record; consider Nagios XI if its pricing model or fit matches your environment better. Side-by-side table below.
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Six criteria, each scored 0–10 on the same scale from real review data, public pricing and feature coverage. See our methodology →
| Criterion | Datadog | Nagios XI |
|---|---|---|
| Editorial | 8.4 | 8.0 |
| User reviews | 8.6 | 9.0 |
| Adoption | 7.2 | 4.6 |
| Affordability | 9.5 | 9.5 |
| Feature breadth | 6.0 | 6.0 |
| Ease of trial | 10.0 | 10.0 |
| Datadog | Nagios XI | |
|---|---|---|
| Starting price | $5/host/mo | $2595/one-time (100 nodes, Standard) |
| Pricing model | per device | per device |
| Free trial / tier | Free tier + 14 days | Free tier + 30 days |
| Best for | Cloud-native teams wanting unified network, infrastructure, and application observability as SaaS | Teams wanting on-prem, perpetually-licensed infrastructure monitoring with a free open-source core |
| Deployment | Cloud | On-prem |
| G2 rating | 4.3/5 (545) | 4.5/5 (55) |
| Capterra rating | — | — |
| Our score | 8.4 | 8.0 |
You need cloud-native teams wanting unified network, infrastructure, and application observability as saas.
You need teams wanting on-prem, perpetually-licensed infrastructure monitoring with a free open-source core.
Datadog bills on a per device model from $5/host/mo (free tier available), while Nagios XI uses a per device model from $2595/one-time (100 nodes, Standard) (free tier available). Because the models differ, the cheaper option flips depending on your fleet size — model both at your seat/endpoint count.
Datadog ships 6 headline capabilities (Cloud Network Monitoring (flows), Network Device Monitoring (SNMP), Unified infra + APM + logs, 800+ integrations) and deploys Cloud. Nagios XI ships 6 (SNMP + network device monitoring, Perpetual on-prem licensing, Event-driven remediation, Free open-source core (Nagios Core)), deploying On-prem.
Datadog holds 4.3/5 (~545 G2 reviews); Nagios XI holds 4.5/5 (~55 G2 reviews). On our data-weighted score, Datadog edges ahead (8.4 vs 8.0/10). Pick Nagios XI instead when teams wanting on-prem, perpetually-licensed infrastructure monitoring with a free open-source core. See Datadog alternatives or Nagios XI alternatives.