Does this require any external package like json_serializable?

No. The generated Dart code is 100% pure Dart and requires zero external packages or build_runner code generation. It uses standard Dart language features (factory constructors and Map ).

Is this compatible with Flutter 3.x and Dart 3.x?

Yes. The code strictly enforces Dart sound null safety, requires no null checks on non-nullable fields, and passes dart analyze cleanly.

JSON to Dart Model Converter

Convert JSON payloads into null-safe Dart classes for Flutter with required constructors, fromJson() factory, toJson() serialization, and nested models.

Target:

Load Template:

JSON Input21 lines · 507 chars

Dart (Flutter).dart

Generated Dart (Flutter) code will appear here

Paste or type valid JSON on the left to see instant, production-ready models.

Ready to compile · Deterministic output.dart

100% Client-Side Privacy: Your JSON is parsed and compiled entirely in your browser using local Web APIs. Nothing is sent to any server.

Zero Network Transfer

What is the JSON to Dart Converter?

The PriyGop JSON to Dart Converter generates production-ready, null-safe Dart classes for Flutter and Dart backend applications. It creates immutable classes withfinal fields, named constructors with required modifiers, and fully typed fromJson() and toJson() serialization methods.

Dart & Flutter Generation Features

Full Null Safety: Mandatory fields are non-nullable; optional fields are marked with ?.
Named Constructors: Uses required this.field for non-nullable properties.
fromJson() Factory: Automatically handles child model parsing and List.map transformations.
toJson() Method: Produces a Map<String, dynamic> for HTTP POST requests and state caching.

Our Tool Features

Why developers and engineers prefer this tool for everyday development workflows.

Cross-Device Compatibility

Works seamlessly on all modern desktop, tablet, and mobile browsers including Chrome, Firefox, Safari, Edge on Windows, macOS, Linux, Android, and iOS.

Fast In-Browser Execution

Processes your data in real-time directly inside your browser. No queue wait times, no network round-trips, and zero latency.

100% Client-Side Privacy

Your code, tokens, passwords, and files are never transmitted to any external server or saved in logs. Everything runs locally in memory.

Instant File & Clipboard Input

Supports one-click sample loading, file drag-and-drop, and pasting directly from your clipboard (Ctrl + V) for effortless workflows.

Strict Standards Compliant

Built strictly according to official specifications (RFCs, W3C, ISO, and standard cryptographic algorithms) ensuring accurate output every time.

Unlimited Free Usage

No registration, no accounts, no subscriptions, and no hidden daily quotas. Use this tool as many times as you need without restrictions.

Recent Updates & Improvements

Continuously maintained and improved based on developer feedback.

Client-Side Speed & Performance UpgradeRecent Update

Optimized processing algorithms with Web Workers and native browser APIs (SubtleCrypto, Canvas 2D) for instantaneous zero-latency execution.

Clipboard Paste & Drag-and-Drop AddedFeature Added

Added instant clipboard pasting (Ctrl + V) and drag-and-drop file support to accelerate developer productivity without manual downloads.

Enhanced Mobile & Touch Device ExperienceUI/UX Update

Redesigned responsive touch controls, flexible copy buttons, and camera preview framing for mobile and tablet browsers.

How To Use JSON to Dart Model Converter Online?

Follow these quick steps to get instant, accurate results in seconds.

Input JSON Data

Paste your API response or local JSON snippet.

Paste any valid JSON string into the editor.
Click 'Sample' to view an example nested user profile.

JSON PayloadClient-Side

{
  "id": 101,
  "title": "Flutter App",
  "rating": 4.9
}

Instant ExecutionReady

Review Dart Class

Inspect constructor, fromJson, and toJson implementations.

Fields are marked final by default for immutable Flutter state management.
Doubles are safely converted using '(json["..."] as num).toDouble()'.

Dart OutputClient-Side

factory Product.fromJson(Map<String, dynamic> json) => ...

Instant ExecutionReady

Download Dart File (.dart)

Save the model directly into your Flutter /lib/models folder.

Click 'Copy Code' or 'Download' to save the .dart file.

Usage in FlutterClient-Side

final product = Product.fromJson(jsonDecode(response.body));

Instant ExecutionReady

Supported Formats & Syntax Examples

Common input data types and real-world representations supported by this tool.

Dart Class with fromJson & toJson

Flutter

Null-safe class with complete serialization methods.

Example Syntax

class User {
  final int id;
  final String userName;
  final String? email;

  User({
    required this.id,
    required this.userName,
    this.email,
  });

  factory User.fromJson(Map<String, dynamic> json) {
    return User(
      id: json['id'] as int,
      userName: json['user_name'] as String,
      email: json['email'] as String?,
    );
  }

  Map<String, dynamic> toJson() {
    return {
      'id': id,
      'user_name': userName,
      'email': email,
    };
  }
}

Analyzes cleanly with dart analyze and conforms to Flutter effective Dart guidelines.

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class User { final int id; final String userName; final String? email; User({ required this.id, required this.userName, this.email, }); factory User.fromJson(Map<String, dynamic> json) { return User( id: json['id'] as int, userName: json['user_name'] as String, email: json['email'] as String?, ); } Map<String, dynamic> toJson() { return { 'id': id, 'user_name': userName, 'email': email, }; } }