Announcing Workers automatic tracing -- now in open beta

Workers gains automatic, OpenTelemetry-compatible tracing in open beta

Cloudflare has opened a public beta for tracing on Workers, giving developers automatic instrumentation for every invocation without code changes, setup, or manual configuration. The feature is designed to answer questions that previously required digging through logs: which calls are slow, which database queries take longest, and what happened inside a request that produced an error.

Workers traces capture each invocation as a hierarchy of OpenTelemetry-compliant spans, each with timing and contextual attributes. Child spans nest under parent spans to show sub-operations and dependencies, giving a visual map of the request flow from entry to completion.

Instrumentation handled inside the runtime

Historically, getting distributed tracing into an application meant integrating third-party SDKs, wrapping database and API calls in instrumentation code, and debugging configuration files before a single span appeared. The implementation overhead often pushed observability aside until an incident made it urgent.

Cloudflare's approach bypasses that entirely: the workerd runtime automatically instruments every I/O operation in a Worker. Application code stays clean, and the runtime handles span creation and attribute capture.

What gets traced today

• Binding calls: interactions with Worker bindings including KV reads/writes, R2 object storage operations, and Durable Object invocations.
• Fetch calls: outbound HTTP requests, with timing, status codes, and request metadata captured automatically.
• Handler calls: fetch, scheduled, and queue handlers that receive external inputs, so you can see how each invocation enters the Worker.

Each span carries available attributes automatically. An R2 binding call such as get or put will include operation type, any error, the object key, and duration — context that defeats the need to log every detail manually.

Cloudflare plans to expand span attributes and add cross-Worker and external-service trace propagation. The complete list of instrumented spans and attributes is in the documentation.

Exploring traces in the dashboard

Traces are surfaced in the Workers Observability dashboard alongside existing logs. From a specific Worker you can list all trace events in a time window, then open an invocation to see each span's duration and attributes. The dashboard also supports querying across all Workers on an account, so issues spanning multiple applications can be isolated without switching context.

Enabling traces on a Workers application requires setting the configuration shown below:

Sending traces to third-party providers

Teams that need Workers telemetry alongside data from other services can export traces directly to any OpenTelemetry Protocol (OTLP) provider with an available endpoint, including Honeycomb, Grafana, and Sentry. Exports support OTLP-formatted logs as well, carrying the same trace ID so third-party platforms can correlate log entries with their corresponding spans automatically.

To export, configure an OTLP endpoint destination in the Cloudflare dashboard. Each destination can have a custom name and custom headers for API keys or configuration. With the destination set — honeycomb-tracing for example — the wrangler.jsonc snippet below enables export after deployment:

Roadmap: propagation, custom spans, and event export

The beta covers automatic runtime instrumentation only. Cloudflare says the following are in development:

• More spans and attributes across the Workers platform.
• Trace context propagation following W3C standards, so traces link across services inside and outside Cloudflare automatically.
• Custom spans and attributes for visibility into application-specific logic.
• Metrics export, covering both infrastructure metrics (request volume, error rates, execution duration) and custom application metrics.

Pricing during and after beta

Both viewing traces in the dashboard and exporting them to third parties are free during the beta. On January 15, 2026, Cloudflare will charge for tracing and log events as follows:

Viewing traces in the dashboard — available on Workers Free and Paid plans:

Exporting traces and logs — requires a Workers Paid subscription, priced per span or log event with inclusions as shown:

Documentation covers setup, current limitations, and upcoming capabilities. Cloudflare is also collecting feedback and feature requests in a GitHub discussion for the beta period.