What problem does it solve?
Writing correct n8n expression syntax can be tricky due to the need for {{}} expressions, the webhook data structure (webhook data is under .body), and referencing other nodes with accurate, case-sensitive names. This guide clarifies those pitfalls and provides a structured path to reliable expression usage.
Core Features & Use Cases
- Formula format mastery: always wrap expressions in double curly braces and avoid common errors.
- Core variables and node references: use $json, $node, $now, and $env to access data across nodes while respecting bracket notation for spaces and case-sensitivity.
- Webhook data handling: access user data from the webhook payload via {{$json.body.field}} and validate paths with examples across real-world scenarios.
- Debugging and validation: practical rules to diagnose missing braces, incorrect paths, and code-node distinctions, plus a quick-reference of common mistakes.
- Real-world patterns: dynamic URLs, concatenation via automatic expression joining, and safe use of environment variables.
Quick Start
Start by writing expressions with {{}} that reference $json and $node data, for example {{$json.body.name}}.
