Trace executions with OpenTelemetry

This feature is still under development

• Initially available from 2.19.0

• Open telemetry formatted metrics will be coming soon

n8n can emit OpenTelemetry traces for workflow and node executions. Use these traces to monitor execution latency, debug failures, and track requests across services in your observability stack.

Watch an overview of OpenTelemetry tracing in n8n:

What you get

When you turn on tracing, n8n exports two kinds of spans for each execution:

• workflow.execute: One span per workflow execution. It records the workflow ID, name, version, node count, execution mode, status, and any error type.

• node.execute: One span per node execution, nested inside its workflow span. It records the node ID, name, type, version, and the number of input and output items.

Each span includes resource attributes that identify the n8n instance:

• service.name (default n8n)

• service.version (the n8n version)

• n8n.instance.id

• n8n.instance.role (for example, main, worker, or webhook)

n8n also handles trace context propagation:

• Inbound: If a webhook request includes a W3C traceparent header, n8n uses it as the parent for the workflow span. This links the n8n workflow trace to the upstream caller.

• Outbound: HTTP Request nodes (and other nodes that use the n8n HTTP helpers) can inject a traceparent header into outbound requests. Downstream services that support W3C trace context can therefore continue the trace.

• Sub-workflows: A sub-workflow's span uses the parent workflow's span as its parent.

• Resumed workflows: When a workflow resumes after a wait, the new span links back to the previous span using a span link.

Enable tracing in the UI

Available from n8n v2.27.0

You need to be an instance owner or admin to configure OpenTelemetry in the UI.

Instead of setting environment variables, you can configure tracing from Settings > OpenTelemetry. n8n applies your changes without a restart, and reloads them across workers and webhook processors in queue mode.

To configure tracing:

1. Select Settings > OpenTelemetry.

2. Turn on Enable OpenTelemetry.

3. Under Collector connection, enter your OTLP endpoint and any other connection details.

4. Under Tracing, set your sampling and span options.

5. Select Save settings.

To check that n8n can reach your collector, select Send test trace under Verify configuration. n8n sends a single test span and reports whether the collector accepted it. You can run this before or after you save.

Each field maps to an environment variable, shown in the field's tooltip. For the full list, see OpenTelemetry environment variables.

Environment variables take precedence

If you set an option with an environment variable, n8n uses that value and disables the matching field in the UI. To manage a setting from the UI, leave its environment variable unset. When n8n restarts, environment variables override the values saved in the UI.

Enable tracing with environment variables

Set the following environment variables on each n8n instance you want workflow tracing enabled (main, workers, and webhook processors):

export N8N_OTEL_ENABLED=true
export N8N_OTEL_EXPORTER_OTLP_ENDPOINT=http://<your-collector-host>:4318

Restart n8n. The instance starts exporting spans over OTLP HTTP using the Protobuf encoding.

n8n appends /v1/traces to the endpoint by default. Point N8N_OTEL_EXPORTER_OTLP_ENDPOINT at the base URL of your collector, not the traces path.

If your collector needs authentication, set N8N_OTEL_EXPORTER_OTLP_HEADERS to a comma-separated list of key=value pairs:

export N8N_OTEL_EXPORTER_OTLP_HEADERS="authorization=Bearer <your-token>,x-tenant=acme"

// For added protection - It is recommended to use the `_FILE` postfix if you are putting a token in here:
export N8N_OTEL_EXPORTER_OTLP_HEADERS_FILE=/mnt/otel-headers

For the full list of supported variables, refer to OpenTelemetry environment variables.

Queue mode

In queue mode, the OpenTelemetry variables must be set on all instances. Trace context is propagated between instances.

Sampling

By default, n8n exports every trace. To reduce volume in busy instances, set N8N_OTEL_TRACES_SAMPLE_RATE to a value between 0 and 1:

# Export 10% of traces <a href="#export-10percent-of-traces" id="export-10percent-of-traces"></a>
export N8N_OTEL_TRACES_SAMPLE_RATE=0.1

n8n uses a trace ID ratio sampler, so the same trace ID is either fully sampled or fully dropped across all spans in the trace.

By default, n8n only outputs traces for production executions. To output traces for all workflow executions, set N8N_OTEL_TRACES_PRODUCTION_ONLY=false.

Reduce span volume

Each node in a workflow produces its own span. For workflows with lots of nodes, this can produce more data than you need. To export only workflow-level spans, set:

export N8N_OTEL_TRACES_INCLUDE_NODE_SPANS=false

To stop n8n from injecting traceparent headers into outbound HTTP requests, set:

export N8N_OTEL_TRACES_INJECT_OUTBOUND=false

Custom span attributes

You can add custom attributes to project, workflow, and node spans. n8n exports each custom attribute as an OpenTelemetry span attribute to your configured observability backend.

Feature availability

Custom span attributes are available on Enterprise plans.

Don't include secrets, personal data, or other sensitive values in attribute values.

n8n supports the following custom attribute levels:

Level	Configure in	Exported span	Attribute prefix
Project	Project settings	workflow.execute	n8n.project.custom.<key>
Workflow	Workflow settings	workflow.execute	n8n.workflow.custom.<key>
Node	Node Settings tab	node.execute	n8n.node.custom.<key>

Project and workflow custom span attributes are available from n8n 2.24.0. Node custom span attributes are available from n8n 2.22.0.

Add project span attributes

To add project-level span attributes:

1. Open a project.

2. Select Project settings.

3. Under Custom Span Attributes, add one or more span attributes.

4. Select Save.

Use plain text for project attribute values.

Add workflow span attributes

To add workflow-level span attributes:

1. Open the workflow.

2. Open Workflow settings.

3. Under Custom Span Attributes, select Configure.

4. Add one or more span attributes.

5. Select Save.

Use plain text for workflow attribute values.

Add node span attributes

To add node-level span attributes:

1. Open the node and select the Settings tab.

2. Under Custom Span Attributes, select Add Attribute.

3. Enter a Key. Keys must be plain text.

4. Enter a Value. Values can be plain text or expressions, such as ={{ $json.environment }}.

Node attribute values must resolve to a string, number, or boolean.

Add attributes programmatically in a custom node

If you're building a custom node, you can attach custom key-value pairs from code. Call setMetadata from the node's execute method:

async execute(this: IExecuteFunctions): Promise<INodeExecutionData[][]> {
	this.setMetadata({
		tracing: {
			'llm.model': 'gpt-4o',
			'llm.token.input': 1500,
			'llm.token.output': 340,
		},
	});

	return [this.getInputData()];
}

n8n prefixes each key with n8n.node.custom. on the exported span. Values must be strings, numbers, or boolean.

This API isn't available from the Code node. It's intended for node authors who want to enrich spans with domain-specific data.

If a node sets an attribute key here that's also configured as a custom node span attribute, the programmatic value takes precedence.

Try it out with Jaeger

You can send traces to a local Jaeger instance to see them in action.

1. Save the following as docker-compose.yml:

services:
  jaeger:
    image: jaegertracing/jaeger:latest
    ports:
      - "16686:16686" # UI
      - "4317:4317"   # OTLP gRPC
      - "4318:4318"   # OTLP HTTP

1. Start Jaeger:

docker compose up -d

1. Start n8n with tracing turned on and pointed at Jaeger. Refer to starting n8n for setup details:

N8N_OTEL_ENABLED=true N8N_OTEL_EXPORTER_OTLP_ENDPOINT=http://127.0.0.1:4318 n8n start

1. Run a workflow, then open the Jaeger UI at http://localhost:16686 - Select "n8n" as service" and click "Find traces" to see the OpenTelemetry traces emitted by n8n.

Span attributes

Workflow and node spans include the following n8n-specific attributes.

Workflow span (workflow.execute)

Attribute	Description
n8n.workflow.id	Workflow ID.
n8n.workflow.name	Workflow name.
n8n.workflow.version_id	Workflow version ID.
n8n.workflow.node_count	Number of nodes in the workflow.
n8n.project.id	Project ID. Available from n8n 2.23.0.
n8n.execution.id	Execution ID.
n8n.execution.mode	Execution mode (for example, manual, webhook, trigger, retry).
n8n.execution.status	Final execution status.
n8n.execution.is_retry	true if the execution is a retry.
n8n.execution.retry_of	The original execution ID, when the execution is a retry.
n8n.execution.error_type	Error class name, set when the execution fails.
n8n.continuation.reason	Set on a span link when the workflow resumes after a wait.
n8n.project.custom.<key>	Custom attributes set through project-level custom span attributes.
n8n.workflow.custom.<key>	Custom attributes set through workflow-level custom span attributes.

Node span (node.execute)

Attribute	Description
n8n.node.id	Node ID.
n8n.node.name	Node name.
n8n.node.type	Node type (for example, n8n-nodes-base.httpRequest).
n8n.node.type_version	Node type version.
n8n.node.items.input	Number of input items the node received.
n8n.node.items.output	Number of output items the node produced.
n8n.node.termination_reason	Why a node span ended without a normal completion (for example, workflow_cancelled).
n8n.node.custom.<key>	Custom attributes set through node-level custom span attributes in the node settings or metadata.tracing in custom node code.

When a node fails, n8n records an exception event on the span with the standard OpenTelemetry exception attributes (exception.type, exception.message, exception.stacktrace).

Troubleshooting

No traces appear in your backend

If n8n can't reach the OTLP endpoint at startup, it logs an error:

Failed to connect to OpenTelemetry OTLP endpoint during startup

Check that:

• N8N_OTEL_ENABLED is set to true.

• N8N_OTEL_EXPORTER_OTLP_ENDPOINT points at the base URL of the collector (not the /v1/traces path).

• The collector is reachable from the n8n container or host.

• Any required N8N_OTEL_EXPORTER_OTLP_HEADERS (such as authentication tokens) are set.

n8n logs OpenTelemetry diagnostics at warn level by default. Set N8N_LOG_LEVEL=debug to see more detail.

Custom span attributes are missing

Check that:

• You have an Enterprise license.

• You set N8N_OTEL_ENABLED to true.

• For node-level span attributes, N8N_OTEL_TRACES_INCLUDE_NODE_SPANS isn't set to false.

Worker traces are missing parent context

In queue mode, workers read the parent trace context from the database. If you only set the OpenTelemetry environment variables on the main instance, worker spans won't link to the parent workflow trace. Set the same variables on every instance type.

Related resources

• OpenTelemetry environment variables

• W3C Trace Context specification

• OpenTelemetry Collector documentation

• Logging in n8n

• Monitoring