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JSON Mapper

Transform JSON data between different formats. Two ways to build a transformation map: paste two JSON examples and let the tool auto-generate the mapping, or write/edit the map manually using source -> target syntax.

Quick Start:

  1. Paste Source JSON (the format you have) and Target JSON (the format you want) into the panels below. The Load from URL is for Registered Users.
  2. Click Parse JSON(s) to analyze both structures and auto-generate the manual mapping editor with fields already linked.
  3. Review links in Manual mapping, connect unlinked fields, then click Build Map to build the transformation map — or write/edit the map directly in the Transformation Map panel.
  4. Replace Source with real data, click Apply Map to transform, then Save the output (Registered Users).
💡 Tips:
1. Enter the same values in the source and target JSON elements to automatically create mappings. For example, if you want to map a field called firstName in your source JSON to first_name in your target JSON, you can set both values to John. This way, when you click Parse JSON(s), the tool will recognize that these fields are matched on their identical values.
2. Use Simplify to reduce array items to unique elements only. For example, if you have a catalog of products it will leave just one of them, merging any properties of products.
Source
Target
Ready. Paste JSON into both panels, then click Parse JSON.

When you click Parse JSON(s), paths are linked automatically in priority order:

  1. Identical paths — source and target paths match exactly
  2. Identical values — fields contain the same example value
  3. Matching keys — property names correspond

After automatic linking you can continue with manual mapping. Choose one of the following methods:

  • Source-first: Click a source path, then pick an unlinked target from the list that appears.
  • Target-first: Click a target path, then click the desired source path to establish the link.

To Remove links:

  • Remove source: Click the delete button (left) to remove the source path from the mapping. The target becomes available again. Use Parse JSON to restore removed source paths.
  • Unlink target: Click the chain button (center) to unlink the target from the source. The source path stays in the mapping.
Manual mapping
Link JSON paths from your source (left side) to target (right side) fields. Click Build Map when done to generate the transformation map.
Transformation Map
The transformation map defines how fields should be transformed. You can edit the map directly or save/load them for reuse (Subscribers only). Once created, use this map to apply transformations to your data files.