The best open-source Datadog alternative in 2026 depends on what you actually use Datadog for. If you want the full three-pillars suite (metrics, traces, and logs in one app), SigNoz is the closest open-source swap. If you just need to know “is my server healthy,” Beszel does that with a 10MB agent for a flat $3/mo. For deep one-second metrics, Netdata; for custom dashboards and PromQL, Prometheus plus Grafana; for uptime and status pages, Uptime Kuma. The seven tools below are sorted by how much of Datadog they replace, with real 2026 prices and an honest note on what each one costs to actually run.
Why people leave Datadog: the bill stacks per host AND per product
Datadog is genuinely good software. The reason people go looking for alternatives is almost always the same one: the pricing model.
Datadog bills two ways at once. Every product is metered separately, and most of them are priced per host. So a single server you want fully observed does not cost you one line item. It costs you several, stacked:
| Datadog product | Price (annual) | What it covers |
|---|---|---|
| Infrastructure (Pro) | $15 / host / mo | Host + container metrics, 15-month retention |
| Infrastructure (Enterprise) | $23 / host / mo | Adds live processes, advanced features |
| APM (Pro) | $35 / host / mo | Distributed traces, 150GB spans/host |
| Continuous Profiler | $19 / host / mo | Code-level profiling (sold separately from APM) |
| Log Management | $0.10 / GB ingest + $1.70 / million events indexed | Two separate meters on the same logs |
Add the published list prices for one host you want fully monitored: Infrastructure Pro ($15) + APM Pro ($35) + Continuous Profiler ($19) lands at about $69 per host per month, before you have ingested a single log line. Logs are their own two meters on top, custom metrics are extra again, and the volume discounts do not start until 500+ hosts. The free tier stops at 5 hosts with 1-day retention, which is fine for a toy and useless for anything real.
For a homelab, a side project, or a small fleet of 1-20 servers, that math is brutal. You are paying enterprise observability rates to answer “is my CPU OK?”
The second reason is data ownership. With Datadog, your metrics, traces, and logs all live on someone else’s infrastructure. Self-hosting keeps them on a machine you control. For a lot of teams in 2026, that alone is the deciding factor.
Here are the seven open-source tools that replace Datadog, layer by layer.
1. SigNoz: the all-in-one open-source Datadog replacement
SigNoz is the one tool on this list built to replace Datadog wholesale rather than one slice of it. It is OpenTelemetry-native and gives you metrics, traces, logs, dashboards, and alerts in a single app, which is exactly the “three pillars in one pane” pitch Datadog sells.
License: The core is MIT, so the community edition is genuinely free to self-host. A few enterprise features (SAML/OIDC SSO, fine-grained RBAC, ingest controls) live under a separate SigNoz Enterprise license, but the MIT core is a complete, working observability platform on its own.
What it costs: Self-hosted is free (you pay only for the server). SigNoz Cloud is usage-based at $0.30/GB for logs, $0.30/GB for traces, and $0.10 per million metric samples, with a Teams plan from $49/mo that includes $49 of usage. Enterprise starts at $4,000/mo.
The catch: SigNoz stores everything in ClickHouse, so it is heavyweight to self-host. A quick evaluation needs a few GB of RAM, but the documented production reference architecture runs ClickHouse plus PostgreSQL plus ZooKeeper across tens of cores and 150GB+ of RAM. This is not a single-binary tool you drop on a Raspberry Pi.
Best for: Teams that genuinely use Datadog’s full APM-plus-logs-plus-metrics suite and want to own the stack. If you only ever looked at the infrastructure tab, SigNoz is overkill, and the lighter tools below will serve you better and cheaper.
2. Beszel: the lightweight infrastructure-metrics replacement
If what you actually used in Datadog was the Infrastructure tab (CPU, memory, disk, network, container stats), Beszel replaces that one job at a tiny fraction of the cost and complexity.
Beszel is a single Go binary. The agent uses roughly 10-15MB of RAM at idle, versus the hundreds of megabytes a Datadog agent plus its integrations pull. You deploy a hub, run one command per server, and metrics start flowing in under five minutes. No YAML, no query language, no per-host invoice.
What it monitors: CPU, memory, disk, network, temperature, GPU, per-container Docker stats, systemd service health, S.M.A.R.T. disk health, and disk I/O detail, all with historical graphs and threshold alerts.
What it costs: The software is MIT and free. The only cost is the small server it runs on. On InstaPods it is a one-click $3/mo deploy, and that one pod watches as many servers as you point agents at, with no per-host billing. Compare that to Datadog Infrastructure at $15-23 per host per month and the gap is the whole point.
Best for: Homelabs, small VPS fleets, and anyone who left Datadog because they were paying APM-suite money to watch four servers. This is the most common landing spot for people escaping the per-host model.
3. Netdata: deep one-second metrics with anomaly detection
Netdata is the closest open-source match for Datadog’s depth on the metrics side. It collects 2,000+ metrics at one-second resolution with built-in machine-learning anomaly detection, which is the feature most people think only Datadog has.
Resource cost: Netdata agents use 200-500MB of RAM per node, much heavier than Beszel but still local-first. The Netdata Cloud free Community tier covers 5 nodes; the paid Business plan is $4.50 per node per month billed annually, which undercuts Datadog Infrastructure by a wide margin.
The trade-off: Netdata shows thousands of charts by default. For deep observability that is a feature. For “is my server OK” it is information overload. Choose Netdata when you want one-second granularity and anomaly detection without Datadog’s invoice.
Best for: Teams that need genuinely deep metrics and used Datadog for its resolution, not just its dashboards.
4. Prometheus + Grafana: the customizable standard
The Prometheus plus Grafana stack is the open-source default for production metrics, and it is what most Datadog refugees who need real customization end up on. PromQL gives you the query power, Grafana gives you the dashboards, and the ecosystem plugs into nearly anything.
The cost: Flexibility has a setup tax. A full stack is Prometheus (scraping) plus node_exporter (host metrics) plus Grafana (visualization), each with its own config, totaling 500MB-1GB+ of RAM and a few hours to a working dashboard. Grafana Cloud starts free at 10,000 active metric series, but a single Docker host can generate 5,000+ series, so three boxes push you into the paid tier at $8 per additional 1,000 series.
Best for: SREs and teams that consider PromQL a feature, not a barrier, and who need custom dashboards, multi-source views, or alerting routed to PagerDuty.
5. Zabbix: the enterprise infrastructure and network monitor
Zabbix is the heavyweight open-source option for large, mixed estates: SNMP network gear, distributed proxies, auto-discovery, and templated alerting across thousands of devices. It is fully free and open source with no per-host fees at all, which is its big advantage over Datadog at scale.
The trade-off: Zabbix runs as a full server plus database plus web frontend, so it wants real resources and real setup time. It is the right call when you are monitoring network infrastructure and a large server fleet, and overkill when you have a handful of VPS boxes.
Best for: IT teams replacing Datadog across a large, heterogeneous fleet including network hardware.
6. Uptime Kuma: the synthetics and status-page replacement
Datadog Synthetics and uptime checks have a clean open-source answer in Uptime Kuma. It monitors whether your services are actually reachable (HTTP, TCP, DNS, ping, SSL, gRPC, MQTT), with 90+ notification channels, built-in status pages, and SSL-expiry alerts.
It uses 30-50MB of RAM, is MIT-licensed, and sets up in about five minutes. This is the layer the metrics tools above do not cover: a server at 10% CPU is meaningless if your site is returning 502s, and Uptime Kuma is what tells you the moment that happens. On InstaPods it is another one-click $3/mo deploy.
Best for: Anyone who used Datadog for uptime, synthetic checks, or public status pages. Most people run it alongside an infrastructure tool like Beszel.
7. Grafana Loki (or Dozzle) for the logs layer
The last Datadog product to replace is Log Management, the one with the two stacked meters. There are two open-source paths depending on scale.
For real log aggregation, Grafana Loki is the Prometheus-style log store that pairs with the Grafana you may already be running. For the lightweight case (just reading and searching Docker logs without standing up a log pipeline), Dozzle is a ~10MB web UI that streams container logs in real time with regex and SQL search. Neither one bills you per ingested gigabyte the way Datadog does.
Best for: Loki if you want a queryable, retained log store; Dozzle if you just want to read container logs without SSH-ing into the box.
Open-source Datadog alternatives compared
| Tool | Replaces (Datadog product) | RAM | License | Self-host cost |
|---|---|---|---|---|
| SigNoz | Full suite (metrics + APM + logs) | Few GB to tens of GB (ClickHouse) | MIT core | Free (heavy server) / Cloud from $49/mo |
| Beszel | Infrastructure metrics | ~10-15MB agent | MIT | $3/mo on InstaPods |
| Netdata | Infrastructure metrics (deep) | 200-500MB/node | GPL-3.0+ | Free / Cloud $4.50/node |
| Prometheus + Grafana | Metrics + custom dashboards | 500MB-1GB+ | Apache / AGPL | Free / Grafana Cloud $8 per 1k series |
| Zabbix | Infrastructure + network | 1GB+ (server + DB) | AGPL/GPL | Free (no per-host fee) |
| Uptime Kuma | Synthetics + uptime | 30-50MB | MIT | $3/mo on InstaPods |
| Grafana Loki / Dozzle | Log management | Loki 200MB+ / Dozzle ~10MB | AGPL / MIT | Free |
The catch with self-hosting (and how to skip it)
Every tool above is free software. “Free” does not mean “zero work,” though. Self-hosting means you provision a server, install the tool, configure a reverse proxy, set up SSL, keep it patched, and back it up. That is the same DevOps tax you pay for any self-hosted app, and it is the reason a lot of people stay on Datadog despite the bill.
The middle ground is managed self-hosting: you own the data and run open-source software, but you do not babysit the server. That is what InstaPods does. A Beszel or Uptime Kuma monitoring pod is a one-click $3/mo deploy with HTTPS, SSH access, and no per-host billing, so a full metrics-plus-uptime setup runs about $6/mo flat no matter how many servers you point at it. For the deeper tools (SigNoz, Prometheus, Grafana), you can run them on a larger pod and still keep the flat monthly bill instead of Datadog’s per-host meter.
If you want the longer breakdown of which monitoring tool fits which setup, this guide to the best server monitoring tools tests each one on RAM, setup time, and what it actually monitors.
Which Datadog alternative should you pick?
- You used the whole Datadog suite (metrics + traces + logs): SigNoz, if you have the hardware to run ClickHouse.
- You only ever looked at infrastructure metrics: Beszel for 1-20 servers, Netdata if you need one-second depth.
- You need custom dashboards and PromQL: Prometheus + Grafana.
- You monitor network gear and a big mixed fleet: Zabbix.
- You used Datadog for uptime or status pages: Uptime Kuma.
- You just want the cheapest path off the per-host bill: Deploy Beszel on InstaPods for $3/mo and add Uptime Kuma when you need it.
For most people leaving Datadog, the honest answer is that they were paying enterprise-suite prices for one layer of it. Match the tool to the layer you actually used, host it somewhere with a flat bill, and the monitoring problem gets a lot cheaper.
FAQ
What is the best open-source Datadog alternative in 2026?
It depends on which Datadog products you use. SigNoz is the best all-in-one open-source replacement because it covers metrics, traces, and logs in a single OpenTelemetry-native app, the same way Datadog does. If you only used infrastructure monitoring, Beszel (lightweight, ~10MB agent) or Netdata (deep, one-second metrics) are better and cheaper fits. For custom dashboards, Prometheus plus Grafana is the standard.
Is SigNoz really free?
The SigNoz community edition is MIT-licensed and free to self-host, and it is a complete observability platform on its own. Some enterprise features (SSO, fine-grained RBAC, ingest controls) sit under a separate license, but you do not need them to run metrics, traces, and logs. The real cost of self-hosting SigNoz is the server, since it runs on ClickHouse and is resource-heavy compared to single-binary tools.
How much does it cost to self-host monitoring versus Datadog?
The software is free for every tool here, so the only cost is the server. On InstaPods a Beszel monitoring pod is $3/mo flat and watches as many servers as you connect, and a Beszel plus Uptime Kuma stack is about $6/mo. Datadog, by contrast, bills per host and per product: a single fully-monitored host across Infrastructure Pro ($15), APM Pro ($35), and Continuous Profiler ($19) adds up to roughly $69/mo on list pricing, before logs.
What is the cheapest way to replace Datadog infrastructure monitoring?
Beszel. It replaces the metrics layer most people actually used in Datadog (CPU, memory, disk, network, container stats) with a single Go binary using about 10-15MB of RAM, and there is no per-host fee. Self-host it on any cheap VPS for free, or deploy it managed on InstaPods for a flat $3/mo with HTTPS and SSH included.
