AI JSON Generator
Create perfect, valid JSON from plain English — then publish it as a mock API. Generate mock data, API responses, and complex schemas in seconds.
Go from a text prompt to a live, editable Mock API in seconds. Generate JSON from plain English, edit it, validate it, and publish as a mock REST API.
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Your adventure is about to begin
From Prompt to API in 3 Steps
Describe Your Data
Write a simple prompt in natural language describing the JSON structure you need.
Generate & Edit
Our AI model generates the JSON code. You can then edit the data to fit your exact needs with live validation.
Validate & Launch API
Your JSON is instantly validated. With one click, publish it as a live mock API endpoint to power your apps.
Why Use Our AI JSON Generator?
Instant Mock API Creation
Turn any generated or edited JSON into a live, shareable mock API endpoint in a single click. Perfect for frontend development and demos.
Save Massive Amounts of Time
Stop typing brackets. Generate complex JSON and a live API endpoint in a fraction of the time it takes to do it manually.
Eliminate Syntax Errors
The AI is trained to produce clean, valid JSON. Say goodbye to frustrating debugging sessions caused by a missing comma.
The Perfect Learning Tool
New to JSON? Describe what you want, see how it’s structured correctly, and instantly see how it works as an API.
Examples: Prompts and Outputs
Try these prompts in the generator above. Edit the output as needed, then publish as a mock API.
Users Array
Prompt: “An array of 3 users with id (number), name, email and createdAt ISO date.”
[
{ "id": 1, "name": "Alice Nguyen", "email": "alice@example.com", "createdAt": "2024-09-15T10:21:00Z" },
{ "id": 2, "name": "Ben Ortiz", "email": "ben@example.com", "createdAt": "2024-09-16T08:05:12Z" },
{ "id": 3, "name": "Chloe Park", "email": "chloe@example.com", "createdAt": "2024-09-17T14:39:50Z" }
]Product Catalog
Prompt: “A product object with id, title, price, tags[], and a nested category object { id, name }.”
{
"id": "sku_1024",
"title": "Wireless Headphones",
"price": 79.99,
"tags": ["audio", "bluetooth", "wireless"],
"category": { "id": 7, "name": "Electronics" }
}Blog Post with Author
Prompt: “A blog post with title, slug, author { name,email}, tags[], and published boolean.”
{
"title": "Demystifying JSON Schemas",
"slug": "demystifying-json-schemas",
"author": { "name": "Priya Shah", "email": "priya@example.com" },
"tags": ["json", "schemas", "best-practices"],
"published": true
}Order with Line Items
Prompt: “An order with id, userId, total, and items[] of { sku, name, qty, unitPrice }.”
{
"id": "ord_8451",
"userId": 2,
"total": 129.97,
"items": [
{ "sku": "sku_1024", "name": "Wireless Headphones", "qty": 1, "unitPrice": 79.99 },
{ "sku": "sku_2301", "name": "USB-C Cable", "qty": 2, "unitPrice": 24.99 }
]
}Popular Use Cases
Frontend Prototypes
Mock endpoints to build UI fast without waiting for backend APIs.
API Contracts & Demos
Share realistic JSON responses with stakeholders and teammates.
QA & Automation
Generate consistent test data for CI, integration, and E2E tests.
Learning & Docs
Explain JSON structures, types, and best practices with examples.
No‑Code & Low‑Code
Create data quickly to feed tools like Airtable, Zapier, or Notion.
Education
Teach JSON syntax by moving from natural language to structure.
Prompt Tips for Better JSON
- Be explicit about structure and types: “id:number, name:string, active:boolean”.
- Specify counts/ranges: “array of 5 items”, “2–3 tags per item”.
- Define formats: “ISO date strings”, “price as number”.
- Use nested requirements: “author “author {name,email}” and comments[]”.
- Mention sample values or constraints: “US phone numbers”, “email pattern”.
- Ask for consistency: “unique ids”, “slugs lowercase-with-dashes”.
Supercharge Your Workflow
For an even faster experience, bring the power of our AI generator directly into your browser.
Get the Free Chrome ExtensionFrequently Asked Questions
Is the AI JSON generator really free?
Yes, absolutely. Our tool is free to use, powered by leading open-source AI models. This allows us to offer powerful generation capabilities at no cost, subject to a fair daily rate limit to ensure availability for all users.
Can I create complex, nested JSON?
Yes. The AI excels at handling complex requests. You can ask for nested objects, arrays of objects, and mixed data types. The more specific your prompt, the better the result. For example, try asking for "An array of 2 blog posts, each with a title, author object (with name and email), and an array of tags".
Is the generated JSON guaranteed to be valid?
While the AI has a very high accuracy rate, it can occasionally make a mistake. That's why we built this tool to seamlessly integrate with our core validator. After generation, the code is instantly checked for validity, and any errors are highlighted for you to fix immediately.
Can I turn the generated JSON into a live API?
Yes. After generating or pasting your JSON, you can publish it as a mock REST API and get instant endpoints. Perfect for prototyping, demos, and front-end development.
Can I use my own data instead of AI output?
Absolutely. Paste your own JSON or schema and publish it as an API. You maintain full control over the structure and values.
Can I edit the AI-generated data before publishing?
Yes. You can edit the AI output before turning it into an API. Our validator runs automatically to ensure everything stays valid.
Ready to Get Started?
Choose from our suite of JSON tools to start processing your data right away.
API Tester
Test REST APIs online free. Send GET, POST, PUT, DELETE requests with custom headers, view responses instantly. Ideal for developers, testers & QA teams..
Download JSON
Generate and download JSON files with exact sizes (Bytes, KB, MB). Perfect for testing API limits, uploads, and performance. Client-side only for privacy.
APIs with Fake JSON Data
Test APIs effortlessly with our Dummy API tool. Generate realistic JSON data for real-world scenarios. Try now for seamless API testing
JSON Minifier
Remove whitespace and reduce the size of your JSON files.
JSON to XML
Convert your JSON data to XML format for different applications.
JSON Path Finder
Extract specific data from JSON using path queries. Navigate and explore complex JSON structures easily.