Infrastructure monitoring · cost comparison
Datadog vs self-hosted Prometheus + Grafana: what each actually costs
Datadog on the Infrastructure Pro tier against Prometheus + Grafana running on the smallest server that fits it. Every figure below is computed from the sizing model and the dated prices at the foot of this page, and includes the part most comparisons leave out: your own time.
At 25 servers, self-hosting Prometheus + Grafana costs $124 a month against $375 for Datadog. You are ahead after about a month and $8,568 better off over 36 months, with your own time already priced in.
- Datadog
- $375per month, Infrastructure Pro
- Self-hosted
- $124server, backups and your time
- Server and backups
- $12.00Starter 2 GB, 2 GB RAM
- 36-month difference
- $8,568 saved by self-hosting
- Break-even
- about a monthafter $450 of setup time
The same comparison at every fleet size
Self-hosting has a floor and almost no slope, while per-host monitoring has no floor and a steep slope. That is the whole story, and it is why the answer flips somewhere in this table rather than being the same for everyone.
| Servers monitored | Datadog | Self-hosted | Without valuing your time | Server needed | 36-month difference |
|---|---|---|---|---|---|
| 5 servers | $75.00 | $124 | $12.00 | Starter 2 GB (2 GB) | -$2,232 |
| 10 servers | $150 | $124 | $12.00 | Starter 2 GB (2 GB) | +$468 |
| 25 servers | $375 | $124 | $12.00 | Starter 2 GB (2 GB) | +$8,568 |
| 50 servers | $750 | $124 | $12.00 | Starter 2 GB (2 GB) | +$22,068 |
| 100 servers | $1,500 | $139 | $26.40 | Starter 4 GB (4 GB) | +$48,550 |
| 250 servers | $3,750 | $159 | $46.80 | Starter 8 GB (8 GB) | +$128,815 |
| 500 servers | $7,500 | $159 | $46.80 | Starter 8 GB (8 GB) | +$263,815 |
The balance tips in favour of self-hosting at around 10 servers.
Where the self-hosted money actually goes at 25 servers
| Line item | Per month | What it is |
|---|---|---|
| Server | $10.00 | Starter 2 GB at VPSServer: 1 vCPU, 2 GB RAM, 50 GB disk |
| Backups | $2.00 | Provider snapshots at 20% of the server price. Skipping this is not a saving, it is a bet. |
| Your time | $112 | 1.5 hours a month of updates, upgrades and the occasional broken thing, at $75 an hour |
| Total | $124 | Plus $450 once, for roughly 6 hours of first-time setup |
Datadog at this size costs $375 a month. 25 monitored servers at $15.00 each. This is the annually-billed rate, which is what the vendor's page displayed; paying monthly costs more.
Read this before you price anything
Datadog has a free plan for up to 5 hosts, but it keeps metrics for one day only, against 15 months on Pro. That is not a like-for-like replacement for monitoring you rely on, so the comparison uses Pro even at 5 servers.
What Prometheus + Grafana needs to run at 25 servers
Prometheus collects the metrics and Grafana draws the dashboards, with Alertmanager for alerts and node_exporter on each server. Disk follows Prometheus's own capacity formula at its default 15-day retention: about 1,000 series per server scraped every 15 seconds at 2 bytes per sample is roughly 0.2 GB per server. Memory per server is our estimate for the same series count.
| Resource | Required | How it is derived |
|---|---|---|
| Memory | 1.6 GB | 1 GB for the stack at rest, plus 10 MB per monitored server, plus 25% headroom |
| Disk | 15 GB | 10 GB base, plus 0.2 GB per server |
| vCPU | 2 | The project's own baseline. For this workload memory runs out before the processor does. |
These base figures are an estimate. Prometheus + Grafana does not publish a minimum specification we could cite, so the base memory and disk are derived from the services in its own reference Docker Compose file. Treat them as a starting point and watch the first week of metrics.
What you give up, stated plainly
- Uptime is now yours. Datadog has an operations team on call. Self-hosted, a failed upgrade at 18:00 on a Friday is your evening.
- Backups only exist if you test restoring them. The $2.00 line above buys snapshots, not a rehearsed recovery.
- Prometheus + Grafana is a multi-container stack with a database you have to back up yourself. That is why the maintenance line is 1.5 hours a month rather than zero.
- Licensing: Prometheus is Apache-2.0, but Grafana, used here for the dashboards, is AGPL-3.0. That only matters if you modify Grafana and offer it to others over a network.
- Feature parity is never exact. Prometheus + Grafana covers the core of what teams use Datadog for; the long tail of integrations and enterprise controls is where the gap shows.
Where to put Prometheus + Grafana
1.6 GB of memory and 15 GB of disk is what this needs at 25 servers. The cheapest plan that fits, among the providers whose prices we have read ourselves, is the Starter 2 GB at VPSServer for $10.00 a month.
We are not claiming this is the cheapest server on the internet. It is the cheapest one we can honestly quote. Hetzner Cloud, Vultr and PikaPods publish prices we could not read programmatically, and Hetzner in particular is usually cheaper per gigabyte of memory than anything quoted above. Price them yourself before you commit.
The VPSServer link above is an affiliate link, run through the same programme as our Kamatera link; VPSServer and Kamatera belong to the same group. If you sign up through it we may earn a commission, but the programme does not state an amount for VPSServer. That never changes the computed costs, which server is chosen, or the conclusion of this page. The sizing model and every price source are published in full.
Prometheus + Grafana at a glance
| Licence | Apache License 2.0 |
|---|---|
| Written in | Go |
| GitHub stars | 66,156, checked 2026-09-21 |
| Latest release | v3.14.0 |
| Last commit | 2026-09-21 |
| Ships Docker images | Yes |
| Project | prometheus.io · prometheus/prometheus |
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Every figure on this page, and where it came from
| Input | Value used | Source | Read on |
|---|---|---|---|
| Datadog Infrastructure Pro | USD 15.00 per monitored server per month | vendor pricing page | 2026-09-21 |
| VPSServer Starter 2 GB | $10.00 per month | provider pricing page | 2026-09-21 |
| Engineer time | $75 per hour | our published assumption | — |
| Prometheus + Grafana sizing | 1 GB base, 10 MB per server | derived from its reference Compose stack | — |
Prices move. If the vendor has changed theirs since 2026-09-21, the figures above are stale and the source links are the authority, not us. How we handle that.