YAML to Dart Converter

Paste a YAML document and get Dart classes with typed fields, optional final modifiers, and fromJson/toJson serialization methods.

Last updated: May 28, 2026

Root class: Final fieldsNullable (T?)fromJson / toJson

YAML Input

Generated Dart Classes

class Root {
  final String? name;
  final int? age;
  final bool? active;
  final Address? address;
  final List<String>? tags;

  Root({
    this.name,
    this.age,
    this.active,
    this.address,
    this.tags,
  });

  factory Root.fromJson(Map<String, dynamic> json) {
    return Root(
    name: json['name'] as String?,
    age: json['age'] as int?,
    active: json['active'] as bool?,
    address: json['address'] == null ? null : Address.fromJson(json['address'] as Map<String, dynamic>),
    tags: (json['tags'] as List<dynamic>?)?.cast<String>(),
    );
  }

  Map<String, dynamic> toJson() {
    return {
    'name': name,
    'age': age,
    'active': active,
    'address': address?.toJson(),
    'tags': tags,
    };
  }
}

class Address {
  final String? city;
  final String? zip;

  Address({
    this.city,
    this.zip,
  });

  factory Address.fromJson(Map<String, dynamic> json) {
    return Address(
    city: json['city'] as String?,
    zip: json['zip'] as String?,
    );
  }

  Map<String, dynamic> toJson() {
    return {
    'city': city,
    'zip': zip,
    };
  }
}

Client-Side Processing

Input Data Stays on Device

Instant Local Execution

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What is YAML to Dart Converter?

This tool converts a YAML document into Dart model classes. It parses YAML to JSON internally, then generates Dart classes with typed fields. Nested YAML mappings become nested Dart classes, sequences become List<T>, and fromJson/toJson factories are generated for easy JSON serialization — common in Flutter apps.

How to Use YAML to Dart Converter

Paste YAML into the input panel.

Set a root class name (optional).

Toggle final fields, nullable types, and fromJson/toJson generation.

Copy the generated Dart classes.

Common Use Cases

Generating Flutter model classes from a YAML API example.
Creating Dart models for a config-driven application.
Scaffolding Dart types before writing YAML parsing code.
Producing serializable Dart classes from YAML service definitions.

Example Input and Output

A small YAML mapping becomes a Dart class with fromJson/toJson.

YAML input

name: Alice
age: 30
active: true

Generated Dart class

class Root {
  final String? name;
  final int? age;
  final bool? active;

  Root({
    this.name,
    this.age,
    this.active,
  });

  factory Root.fromJson(Map<String, dynamic> json) {
    return Root(
      name: json['name'] as String?,
      age: json['age'] as int?,
      active: json['active'] as bool?,
    );
  }
}

Tip

For Flutter projects, consider using code generation packages like json_serializable for production serialization instead of hand-written fromJson/toJson.