Generate JSON from Natural Language

AI generate JSON

When you prototype or mock, you don't have to type braces by hand. Describe the object in English or Chinese and get valid JSON.

Pick an object, array, nested shape, or mock template. It fits common shapes like a product, a user profile, or an API response.

No cloud model is called, so you don't need an API Key. Complex business rules and real inventory numbers still need a pass from you.

After you generate, format it, produce a Schema, or use it as Function Calling sample input.

Be specific in the description

List the fields, say object vs array, and mention nested variants if you have them. "Give me a user" yields a generic shape.

This is not real random business data

Local rules assemble the shape. Emails, prices, and stock look plausible, but they are not production stats. For a realistic distribution, edit the template and use Mock.

How to use it

Describe fields and nesting in natural language, or load the product sample.
Pick a template: object, array, nested shape, or Mock.
Click Generate JSON, or use the array / nested buttons.
Scan types. Don't let numbers turn into strings.
Copy the result to Format, Schema, or Structured Output.

When to use it

The frontend has no API yet — invent an object the page can render.
Prepare the first sample for Schema / Zod.
Drop a valid JSON snippet into a blog post or doc.
Pair with Repair: generate the right shape, then compare against broken text.

Keep in mind

It does not call OpenAI or any other cloud API.
Hard constraints, real inventory, and compliance fields must be edited by hand.
If you need many records with the same shape, Batch mock is a better fit.

FAQ

Why don't I need an API Key?

This page builds the shape with local rules. It does not call OpenAI or any other cloud API.

Can it generate complex business JSON?

It's good for medium-complexity objects and arrays. For hard constraints or real data, edit by hand — or generate a Schema and then Mock.

How is this different from JSON Repair?

Generate starts from a description. Repair completes broken or invalid JSON into parseable text.

Is the description uploaded?

No.

Can I describe it in Chinese?

Yes. Chinese and English both assemble the shape from field names and relationships.

Is every result the same?

The shape is stable; fill-in values may follow the template. Don't treat it as an idempotent API.

Can I specify field types?

Say so in the description — "price is a number, tags is a string array" — and it will be closer.

When should I use the Mock page instead?

Describe from scratch here. If you already have a template and only need new values, use Mock.