n8n-expression-syntax

To fix n8n webhook expression errors, reference webhook payload data using {{$json.body}} syntax. Webhook data lives under the .body object, so accessing it directly via $json without the body path causes validation failures.

To reference data from another node in n8n expressions, use the $node variable with the target node name. If the node name contains spaces, apply bracket notation and ensure exact case-sensitivity matching for successful validation.

The correct syntax for n8n expressions requires wrapping variables or code in double curly braces, {{ }}. You can access standard variables like $json for current node data and $node for cross-node references within this structure.

n8n expression validation fails when nested fields are accessed incorrectly due to missing braces or wrong paths. Validate proper {{ }} syntax and ensure accurate data access paths like $json.body.name in the expression editor to resolve it.

Test and debug n8n expressions directly within the expression editor by entering a syntax like {{$json.body.name}}. This validates correct data access, checks for syntax errors, and confirms proper path resolution before running the workflow.