How are types inferred?

The tool walks your JSON structure and infers the corresponding TypeScript types — nested objects become their own interfaces, and arrays become typed lists.

Does this require the Zod library?

No, the Zod schema is generated as plain text code for you to copy into a project that already has Zod installed — this tool has no dependency on it.

Is my JSON uploaded anywhere?

No, type generation happens entirely in your browser.

How does it handle arrays with mixed element types?

Items are merged into one type: numbers and strings become number | string, objects with different keys become one interface, and keys missing from some items are marked optional.

Are optional and nullable fields detected?

Yes. A key missing from some objects in an array becomes optional (?), and a value that is sometimes null becomes a union such as string | null. Tick All optional to mark every field optional.

Can I generate a type alias instead of an interface?

Yes, a toggle lets you switch between generating a TypeScript `interface` or a `type` alias.

Does the Zod schema output include validation like min/max?

No — the schema reflects the shape only (types, optional, nullable, unions), plus an import line and an inferred type. Add .min(), .email() and similar rules yourself.

Can I rename the root type or add export and readonly?

Yes. The toolbar sets the root type name and toggles export, readonly and all-optional.

Processed 100% locally in your browser

JSON to TypeScript & Zod Schema

Generate TypeScript interfaces, type aliases and Zod schemas from JSON, with optional fields and unions detected for you.

Loading tool…

Quick Answer

JSON to TypeScript & Zod Schema lets you: Generate TypeScript interfaces, type aliases and Zod schemas from JSON, with optional fields and unions detected for you. To start, paste or type a JSON object or array in the editor.

How to use this tool

1
Paste your JSON
Paste or type a JSON object or array in the editor.
2
Choose your options
Pick interface or type alias, toggle optional fields, and enable Zod schema generation if needed.
3
Copy or download
Copy the generated TypeScript code or download it as a .d.ts file.

Format & Performance Scorecard

Feature	JSON	TypeScript
Purpose	Data format	Type definitions
Best for	Storing/transmitting data	Compile-time type safety
Validation	Runtime only	Compile-time checks
Common use	API payloads, config	Typed code against API shapes

Frequently Asked Questions

JSON Formatter

A full-screen JSON editor: format, validate, repair, sort keys, and explore as a tree, table or JSONPath query — 100% local.

JSON ↔ YAML

Convert between JSON and YAML in a full-screen editor — anchors, multiline strings and multi-document files included.

JSON to TypeScript & Zod Schema

How to use this tool

Paste your JSON

Choose your options

Copy or download

Format & Performance Scorecard

Frequently Asked Questions

How are types inferred?

Does this require the Zod library?

Is my JSON uploaded anywhere?

How does it handle arrays with mixed element types?

Are optional and nullable fields detected?

Can I generate a type alias instead of an interface?

Does the Zod schema output include validation like min/max?

Can I rename the root type or add export and readonly?

Related Tools

JSON Formatter

JSON ↔ YAML

JSON to TypeScript & Zod Schema

How to use this tool

Paste your JSON

Choose your options

Copy or download

Format & Performance Scorecard

Frequently Asked Questions

How are types inferred?

Does this require the Zod library?

Is my JSON uploaded anywhere?

How does it handle arrays with mixed element types?

Are optional and nullable fields detected?

Can I generate a type alias instead of an interface?

Does the Zod schema output include validation like min/max?

Can I rename the root type or add export and readonly?

Related Tools

JSON Formatter

JSON ↔ YAML