JSON to Dart Converter
ConvertersGenerate Dart classes with fromJson/toJson from a JSON object instantly in your browser. Powered by quicktype-core. UML class diagram view. 100% client-side.
JSON →
Dart
JSONjson
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Dartdart
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Input: 315 chars
About JSON to Dart Converter
The JSON to Dart converter uses `quicktype-core` with `just-types: true` to generate Dart class definitions with typed fields and factory constructors. A post-processing step removes extraneous helpers, keeping the class fields and `fromJson`/`toJson` methods. Output is prettified with js-beautify. The UML class diagram panel shows the inferred class hierarchy.
Features
- ✓Powered by quicktype-core for Dart class generation
- ✓Generates Dart classes with typed fields
- ✓Includes fromJson factory constructors and toJson methods
- ✓Post-processed to remove boilerplate helpers
- ✓UML class diagram view shows the inferred class hierarchy
- ✓Handles nested objects → nested Dart classes
- ✓Handles arrays → List<T> fields
- ✓Nullable fields use T? annotations (Dart 2.12+ null safety)
- ✓Download generated Dart as a .dart file
- ✓Copy output to clipboard in one click
- ✓Web Worker processing — never blocks the UI
- ✓100% client-side — data never leaves your browser
Common Use Cases
- Generating Dart model classes from JSON API responses for Flutter apps
- Creating Dart data models from JSON payloads for http or dio requests
- Scaffolding Dart data classes from JSON configuration files
- Reverse-engineering JSON to Dart types for Flutter state management
Frequently Asked Questions
QDoes the output support null safety?
Yes — nullable fields use the T? syntax introduced in Dart 2.12 (null safety).
QIs my data sent to a server?
No. quicktype-core runs in a Web Worker inside your browser.