OpenTelemetry vs Datadog: standard SDK vs proprietary agent

Short answer

OpenTelemetry is not a competitor to Datadog the way one product competes with another. OpenTelemetry is the standard SDK and wire format; Datadog is a backend that historically required its own SDK and agent. Today Datadog also accepts OTLP, so the practical question is whether to commit to Datadog's agent-led path or stay on the vendor-neutral OTel path that lets you switch backends later.

What each is

OpenTelemetry is a CNCF project: language SDKs, a Collector, and the OTLP wire format. It does not store or visualize anything. You pick a backend (Telemtra, Jaeger + Tempo + Loki, Grafana Cloud, Datadog, New Relic, Honeycomb, etc.) that speaks OTLP.

Datadog is a hosted, opinionated observability product: metrics, APM, logs, RUM, profiling, and security in one UI. Until recently it preferred its own dd-trace SDKs and Datadog Agent. OTLP ingest is now supported but is treated as a secondary path in most language ecosystems.

SDK lock-in vs portability

If you instrument with dd-trace, every change of backend means re-instrumenting every service. If you instrument with OpenTelemetry, the application code stays the same and only the Collector exporter changes. For a small project this is academic; for a service that has shipped to production, it is the difference between "swap a YAML field" and "schedule a quarter of work."

This is the main reason most platform teams started in 2023–2025 prefer OpenTelemetry even if their backend is currently a proprietary product. You write code against the standard once and pick the backend per environment.

Pricing surface

Datadog's pricing has many lines: hosts, APM hosts, indexed logs, ingested logs, custom metrics by cardinality, RUM sessions, etc. The OTel side does not have pricing because it is a standard; the backend (Telemtra, Grafana Cloud, etc.) has its own model. Telemtra's pricing is plan-based ingest and retention — closer to the simpler line items Datadog teams ask for.

Feature breadth

Datadog has more product surface area (RUM, synthetics, security monitoring, profiling, CI visibility). If you need all of those in one vendor, Datadog is one of a small set of single-vendor stops. The trade-off is the bill and the agent footprint.

OpenTelemetry plus a focused OTel-native backend (like Telemtra) gives you logs, traces, metrics, alerts, dashboards, service maps, and ingest-time shaping — the core observability surface — without the bundled features many teams do not use. For most product engineering teams that is the relevant scope.

Using OpenTelemetry with Datadog

If you want OTel instrumentation but Datadog as backend, you have two options. First, point the OpenTelemetry Collector at Datadog via the datadog exporter:

exporters:
  datadog:
    api:
      key: ${env:DD_API_KEY}
      site: datadoghq.com

Second, send OTLP directly to the Datadog Agent (which has an OTLP receiver). Both keep your app code OTel-native and let you change backends later without re-instrumenting.

Where Telemtra fits

Telemtra is the OTel-native backend designed for teams that picked OpenTelemetry instrumentation and want a focused, fast workspace for logs, traces, metrics, and alerts without a six-figure annual commitment. The whole stack is OTLP in: pick HTTP/protobuf for app-direct export or gRPC via a Collector.

For teams currently on Datadog, the migration path is to deploy a Collector that double-writes: ship to both Datadog and Telemtra during a transition window, validate parity, then turn off Datadog. Because both accept OTLP, the application code does not change.

How to choose

Start with OpenTelemetry SDK in all new code regardless of backend. It is the cheapest insurance against future migration.
Pick a backend by the workflows you need. If you need RUM, profiling, and security in one bill, Datadog and the few peers at its scale are the choice. If you need logs, traces, metrics, service maps, and alerts with a clear ingest-based price, Telemtra is the focused choice.
Avoid dd-trace and other vendor SDKs unless you have an explicit reason that overrides portability.

See What is OTLP? and the Collector quickstart for the OTel-native path. Start a free Telemtra workspace to compare the experience side by side.

OpenTelemetry vs Datadog.