Can JSON generate a JavaScript class?
Yes. Class mode creates an ES class for each inferred model and can include a constructor, an ES module export, and a static fromJSON helper.
JSON to JavaScript Converter
Generate JavaScript classes and JSDoc typedefs from JSON.
Generate JavaScript from JSON
Paste sample JSON and generate JavaScript models locally in your browser.
Use an object or an array of objects for model inference.
JavaScript options
Generated code
Generated code will appear here.Convert JSON to JavaScript
Convert a JSON sample into JavaScript classes or JSDoc typedefs for projects that need consistent object shapes without adding TypeScript. The generator recognizes nested objects and arrays while keeping the output in standard JavaScript.
JavaScript does not provide TypeScript-style static types. Class output gives the data a constructor-based runtime structure, while JSDoc output supplies editor-readable type documentation without changing the runtime.
JavaScript classes and JSDoc output
Class mode can add constructors, ES module exports, and a static fromJSON helper. Constructors map original JSON keys to safe property names, including keys that contain hyphens or use snake_case.
JSDoc mode emits typedef and property annotations rather than executable classes. Editors can use those annotations for completion and type hints, but JavaScript still performs no static type enforcement.
JavaScript conversion example
Example JSON input:
{
"user_id": 42,
"profile": {
"display_name": "Ada"
}
}Generated JavaScript output:
export class RootModel {
constructor(source = {}) {
this.userId = source["user_id"];
this.profile = source["profile"];
}
static fromJSON(source) {
return new RootModel(source);
}
}
export class RootModelProfile {
constructor(source = {}) {
this.displayName = source["display_name"];
}
static fromJSON(source) {
return new RootModelProfile(source);
}
}How to generate JavaScript code
- Paste a JSON object or an array of similar objects.
- Enter the root class or typedef name.
- Choose ES class or JSDoc output and adjust constructor, export, fromJSON, and property-name options.
- Generate the JavaScript, then copy it or download the .js file.
Frequently asked questions
How does JavaScript output differ from TypeScript?
JavaScript class output creates runtime code, while TypeScript output creates static type declarations. JavaScript itself does not enforce the inferred property types.
What does a JSDoc typedef provide?
A JSDoc typedef documents the object and property types in regular JavaScript. Compatible editors can use it for hints and checks without producing a runtime class.
What does constructor generation do?
The generated constructor accepts a source object and assigns each JSON value to its safe JavaScript property name. It can be disabled when only a class shell is needed.
Does conversion happen locally?
Yes. The JSON sample and generated JavaScript stay in the browser and are not added to URLs, storage, or remote requests.
Private browser-based conversion
Your JSON input, field names, root model name, and generated JavaScript source stay in this browser. They are not sent to a backend, added to the URL, or saved in local storage or cookies.
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