Logfire is full-stack observability for the agent era: infrastructure monitoring, service maps, APM, logs, metrics, traces, session replay, feature flags, and AI observability in one OpenTelemetry-native product. The agent trace investigator follows every model call, tool call, retry, database query, API request, log, and host signal in one nested trace. For model-call telemetry, Logfire’s 10M-record free tier covers a workload that lists at about $5,125/month in Datadog Agent Observability with 30-day retention—assuming one Logfire record per LLM span. Then Logfire costs $2 per million records, without Datadog’s product-sprawl bill.
| Feature | Logfire | Datadog |
|---|---|---|
| Platform coverage | Infra, APM, logs, metrics, traces, replay, flags, and AI | Comparable coverage across separately activated products |
| Architecture | One OpenTelemetry-native product | Datadog agents or OTLP intake with platform extensions |
| Pricing Model | 10M free; then $2/M records | $15/infra host + $31/APM host + $350/M LLM spans + $150/M for 30-day retention |
| Host Fees | None | Infrastructure and APM billed per host |
| AI/LLM Support | Agents, applications, and infrastructure in one project | Separately billed Agent Observability product |
| Query workflow | PostgreSQL-compatible SQL across all telemetry | Product-specific syntax; DDSQL for supported data |
| MCP server | SQL queries plus dashboards, alerts, and issues | DDSQL MCP toolset (preview) |
| Budget control | Hard price cap on Team+ plans | Usage across separately priced products |
| Scenario | Datadog | Logfire | Savings |
|---|---|---|---|
| 100M LLM spans/month | $50,125/mo | ~$229/mo (Team + 90M records) | ~219x lower |
| 500M LLM spans/month | $250,125/mo | ~$1,029/mo (Team + 490M records) | ~243x lower |
| Infrastructure and APM | $15 + $31/host/month | No host fees | No host tax |
| Monthly budget | Multiple product meters | Hard price cap on Team+ plans | A ceiling you set |
Illustrative US annual-list-price model, checked July 2026. It assumes one Logfire record per LLM inference span and excludes additional Logfire browser, tool, retrieval, API, database, log, metric, and application telemetry. Datadog Agent Observability: $160/month including 100,000 LLM spans, then $3.50 per 10,000; 30-day retention adds $1.50 per 10,000. Logfire Team: $49/month including 10 million records, then $2 per additional million. Datadog infrastructure and APM charges are additional.
Run infrastructure monitoring, service maps, APM, logs, metrics, traces, session replay, feature flags, and AI observability in the same OpenTelemetry-native product. Every signal is available to the same team, in the same project, when an incident crosses from the browser to an API, agent, database, or host.
Start with one agent run, then see every model call, tool call, retry, database query, API request, log, and host signal in its nested trace. Model and agent views surface the pattern; the trace shows exactly why a production run failed.
Logfire's free plan includes 10 million telemetry records each month. If each of those records is an LLM inference span, Datadog Agent Observability with 30-day retention lists at $5,125/month before you add APM, host monitoring, logs, or other Datadog products. On Team and Growth, Logfire remains $2 per additional million records and lets you set a hard price cap.
Datadog's Agent Observability is separately packaged and billed. Logfire puts AI, application, and infrastructure telemetry in the same project and uses PostgreSQL-compatible SQL across it. No moving from product to product—or from query syntax to query syntax—to explain a production failure.
Logfire Cloud, Dedicated, and Self-Hosted run the same product. For sensitive workloads, deploy the official Helm chart in your own Kubernetes environment with your own PostgreSQL and object storage, and keep the same instrumentation, views, SQL, and trace-investigation workflow.
For a model-call-only workload that assumes one Logfire record per LLM span, 100 million LLM spans with 30-day retention list at $50,125/month in Datadog Agent Observability versus about $229/month in Logfire Team: $49/month plus $2 for each of the 90 million records beyond the included 10 million. That is about 219x lower before Datadog infrastructure or APM products. At 500 million LLM spans, the comparison is $250,125 versus about $1,029, or about 243x lower.
Logfire prices telemetry as one stream: 10 million records are included, then Team and Growth charge $2 per additional million with no host fees and a hard price cap. Datadog charges separately for Infrastructure Monitoring hosts, APM hosts, logs, and Agent Observability LLM spans. A modern application can use several of those products at once, so the bill grows with product coverage as well as telemetry volume.
Yes. Logfire is a full-stack observability platform: infrastructure monitoring, service maps, APM, logs, metrics, traces, session replay, feature flags, and AI observability all work together in the same OpenTelemetry-native product. Datadog may still be a fit when you need a specific Datadog-only integration or compliance capability.
Yes. Logfire Enterprise Self-Hosted runs the same product in your own Kubernetes environment via the official Helm chart. Use your own PostgreSQL and object storage while retaining the same instrumentation, views, SQL queries, and agent-trace investigation workflow.
Both platforms support LLM tracing, evaluation, and human review. Logfire is designed for investigating what happened in production: a single nested trace connects model calls, tool calls, retries, database queries, API requests, logs, and host signals. Model and agent views surface the pattern; the underlying trace explains the failure.
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