n8n-expression-syntax

Webhook data in n8n is nested under the body property, so use {{$json.body.fieldName}} rather than {{$json.fieldName}}. The webhook node output separates headers, params, query, and body, which is why root-level access returns undefined.

Expressions appear as literal text when they are not wrapped in double curly braces. Change $json.email to {{$json.email}} so n8n evaluates it instead of treating it as a plain string.

No, Code nodes use direct JavaScript access without curly braces. Write const email = $json.email or use $input.item.json.email instead of the {{ }} expression syntax, which only works in expression fields of other nodes.

Use bracket notation with quotes: {{$node["HTTP Request"].json.data}}. Node names are case-sensitive and must match the workflow exactly, so {{$node["http request"]}} would fail.

Use bracket notation such as {{$json['first name']}} because spaces break dot notation. This also applies to nested paths like {{$json['user data']['phone number']}}.

Avoid expressions in Code nodes, webhook paths, and credential fields. Webhook paths must be static or use URL parameters like :userId, and credentials should use the n8n credential system rather than environment variable expressions.