Expression Variables¶

All variables available in expressions.

Current Item Variables¶

$json¶

The current item's JSON data:

// Item: { "name": "John", "age": 30 }

{{ $json.name }}      // "John"
{{ $json.age }}       // 30
{{ $json }}           // { "name": "John", "age": 30 }

$item¶

Current item index (0-based):

// Processing 3 items

{{ $item }}  // 0, 1, 2 for each item

$binary¶

Binary data attached to the item:

{{ $binary.data.fileName }}    // "document.pdf"
{{ $binary.data.mimeType }}    // "application/pdf"
{{ $binary.data.fileSize }}    // 1024

Input Data Variables¶

$input¶

Access all input data:

{{ $input.all }}              // Array of all input items
{{ $input.first }}            // First input item
{{ $input.last }}             // Last input item
{{ $input.item }}             // Current input item

$input.all Example¶

// Sum all values
{{ $input.all.reduce((sum, item) => sum + item.json.value, 0) }}

Node Access Variables¶

$node¶

Access output from any node by name:

{{ $node["Node Name"].json.field }}

Examples¶

// Access HTTP Request output
{{ $node["Fetch Users"].json.users }}

// Access Set node output
{{ $node["Format Data"].json.message }}

// Access first item from node
{{ $node["Get Data"].json }}

Multiple Items from Node¶

// Get all items from a node
{{ $node["Fetch Data"].all }}

// Get specific item
{{ $node["Fetch Data"].item(2).json.field }}

Environment Variables¶

$env¶

Access environment variables:

{{ $env.API_KEY }}
{{ $env.DATABASE_URL }}
{{ $env.NODE_ENV }}

Usage Example¶

{
  "parameters": {
    "url": "{{ $env.API_BASE_URL }}/users",
    "headers": {
      "Authorization": "Bearer {{ $env.API_TOKEN }}"
    }
  }
}

Date/Time Variables¶

$now¶

Current timestamp (ISO 8601):

{{ $now }}  // "2024-01-15T10:30:00.000Z"

$today¶

Current date (YYYY-MM-DD):

{{ $today }}  // "2024-01-15"

Workflow Variables¶

$workflow¶

Workflow metadata:

{{ $workflow.id }}          // Workflow ID
{{ $workflow.name }}        // Workflow name
{{ $workflow.active }}      // Is active

$execution¶

Current execution info:

{{ $execution.id }}         // Execution ID
{{ $execution.mode }}       // "manual" or "trigger"

Parameter Variables¶

$parameter¶

Access node parameters:

{{ $parameter.url }}
{{ $parameter.method }}

Position Variables¶

$position¶

Node position in workflow:

{{ $position }}  // Node index in execution order

Variable Scope¶

Variable	Scope	Description
`$json`	Per item	Current item data
`$item`	Per item	Item index
`$binary`	Per item	Binary data
`$input`	Per node	All input items
`$node`	Global	Any node's output
`$env`	Global	Environment vars
`$now`	Global	Current time
`$workflow`	Global	Workflow info
`$execution`	Global	Execution info

Complex Examples¶

Conditional Logic¶

{{ $json.status === "active" ? $json.name : "Inactive: " + $json.name }}

Array Operations¶

// Filter and map
{{ $input.all.filter(i => i.json.active).map(i => i.json.name).join(", ") }}

String Building¶

{{ `User ${$json.name} (ID: ${$json.id}) - ${$json.role}` }}

Date Formatting¶

{{ new Date($json.createdAt).toLocaleDateString() }}

Aggregation¶

// Total from all items
{{ $input.all.reduce((sum, i) => sum + i.json.amount, 0) }}

Best Practices¶

Use descriptive node names - Makes $node["Name"] readable
Check for undefined - Use ?. operator
Provide defaults - Use ?? or || operators
Keep expressions simple - Complex logic goes in Code nodes

Common Patterns¶

Safe Field Access¶

{{ $json.user?.profile?.email ?? "[email protected]" }}

Dynamic Field Names¶

{{ $json[$node["Config"].json.fieldName] }}

JSON Stringification¶

{{ JSON.stringify($json.data) }}

Parsing JSON¶

{{ JSON.parse($json.jsonString) }}