Sync & Scheduling

Understanding field mapping rules

Last updated: January 28, 20266 min read

What are Field Mappings?

Field mappings define how data is transferred between source and destination fields during a sync. Each mapping specifies a source field, a destination field, and optionally a transformation rule.

Auto-Mapping

When you create a new sync, Synchr.ai automatically suggests field mappings based on matching field names and compatible data types. Auto-mapped fields are highlighted in blue and can be customized at any time.

Mapping Types

Direct Mapping

The simplest mapping type. The value from the source field is copied directly to the destination field without any transformation. Use this when the fields have the same data type and format.

Transform Mapping

Apply a transformation to the source value before writing it to the destination. Common transformations include:

  • String formatting — Uppercase, lowercase, trim whitespace, concatenate
  • Date formatting — Convert between date formats (ISO 8601, Unix timestamp, etc.)
  • Number formatting — Round, floor, ceil, currency conversion
  • Conditional — Map values based on conditions (if/else logic)

Computed Mapping

Create destination values from multiple source fields using expressions. For example, concatenate firstName and lastName to create a fullName field.

Handling Missing Fields

Configure what happens when a source field is empty or missing:

  • Skip — Do not update the destination field (default)
  • Set to null — Clear the destination field value
  • Use default — Apply a fallback value that you define

Testing Your Mappings

Use the "Preview" button to test your mappings against real data before activating the sync. The preview shows a sample of 10 records with the transformations applied, so you can verify the output matches your expectations.

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