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Data & Dev Config • Zero-Server RAM Execution

Convert JavaScript Object to JSON Online - Free, Local & Instant

Instant JavaScript Object (.js) to JSON (.json) converter. 100% client-side processing in your browser RAM — zero file uploads, full privacy, drag & drop or paste raw text.

JavaScript Object → JSON ⇄ Swap (JSON → JavaScript Object)

Technical Comparison: JavaScript Object vs JSON

Data & Dev Config
Specification JavaScript Object (Source) JSON (Target)
Full Specification ES Module JavaScript Object Literal JavaScript Object Notation
File Extension & MIME .js (text/javascript) .json (application/json)
Data Typing Model Unquoted identifier keys, single-quoted strings, ES export default Strict (strings, numbers, booleans, arrays, objects, null)
Structure & Hierarchy Arbitrarily nested JS objects and arrays Deeply nested trees & arrays
Comments Support Supported (// and /* */) Not supported in RFC 8259 (supported via relaxed parser)
Primary Ecosystem Vite/Webpack configs, TypeScript/JS mock data, Next.js constants REST APIs, web apps, NoSQL document stores, modern configs

JavaScript Object to JSON — Before & After Example

Before (JavaScript Object Input)
const data = [
  {
    id: 1,
    name: 'Alice Johnson',
    email: 'alice@example.com',
    role: 'admin',
    active: true,
    score: 98.5,
    address: {
      city: 'Berlin',
      country: 'DE',
    },
  },
  {
    id: 2,
    name: 'Bob Smith',
    email: 'bob@example.com',
    role: 'editor',
    active: false,
    score: 87,
    address: {
      city: 'Austin',
      country: 'US',
    },
  },
  {
    id: 3,
    name: 'Chiara Rossi',
    email: 'chiara@example.com',
    role: 'viewer',
    active: true,
    score: 91.25,
    address: {
      city: 'Milan',
      country: 'IT',
    },
  },
];

export default data;
After (JSON Output)
[
  {
    "id": 1,
    "name": "Alice Johnson",
    "email": "alice@example.com",
    "role": "admin",
    "active": true,
    "score": 98.5,
    "address": {
      "city": "Berlin",
      "country": "DE"
    }
  },
  {
    "id": 2,
    "name": "Bob Smith",
    "email": "bob@example.com",
    "role": "editor",
    "active": false,
    "score": 87,
    "address": {
      "city": "Austin",
      "country": "US"
    }
  },
  {
    "id": 3,
    "name": "Chiara Rossi",
    "email": "chiara@example.com",
    "role": "viewer",
    "active": true,
    "score": 91.25,
    "address": {
      "city": "Milan",
      "country": "IT"
    }
  }
]

Frequently Asked Questions: JavaScript Object to JSON

How do I convert JavaScript Object to JSON online without uploading sensitive files? ▾

Paste your JavaScript Object data or drag and drop a .js file into the converter above. ZeroUpload parses JavaScript Object and serializes JSON 100% inside your browser RAM using local JavaScript—no bytes are ever sent to an external server.

How are nested objects or tabular columns mapped between JavaScript Object and JSON? ▾

When converting hierarchical structures (Arbitrarily nested JS objects and arrays) and tabular or config formats (Deeply nested trees & arrays), our engine automatically flattens or unflattens dot-separated keys (such as address.city) and preserves numbers, booleans, arrays, and null values.

Is this JavaScript Object to JSON converter free for commercial and production config files? ▾

Yes. The tool is completely free, requires no account or API key, and works offline once loaded. Because execution happens in local memory, it is safe for proprietary JavaScript Object, database exports, and production secrets.

Can I convert JSON back to JavaScript Object? ▾

Yes! Click the "Swap (JSON → JavaScript Object)" button at the top of the workspace or use the reverse converter link at the bottom of this page for bidirectional conversion.