JSON to Strict Type Converter
Instantly convert JSON objects into strict type definitions for TypeScript interfaces, Zod schemas, Rust Serde structs, and Go structs directly in your browser.
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Key Features
- Multi-Language Support: Generate code for TypeScript, Zod, Rust, and Go from a single JSON source.
- Privacy Focused: All processing is done client-side. Your sensitive JSON data is never uploaded to our servers.
- Instant Preview: See the generated type definitions update in real-time as you type or paste JSON.
- Framework Ready: Generates Zod schemas for runtime validation and Rust structs with Serde attributes.
How to Use This Tool
- Paste Data: Copy your raw JSON object and paste it into the left-hand editor panel.
- Choose Language: Use the dropdown menu to select your target output (e.g., TypeScript or Rust).
- Review Output: Check the generated code in the right-hand panel for accuracy.
- Copy & Use: Click the "Copy Code" button and paste the definition directly into your codebase.
Why Use This Tool?
Manually writing type definitions for large or complex JSON responses is tedious and error-prone. Whether you are integrating a third-party API in a React app (TypeScript), validating form data (Zod), or building a backend service (Rust/Go), having strict types is essential for code quality.
This tool automates that process, saving you hours of boilerplate typing and ensuring your types match your data structure exactly. It handles nested objects, arrays, and primitive types seamlessly.
Advanced Usage Tips
- Working with real API responses: Rather than hand-writing a sample payload, copy a real response body from your browser's Network tab so the generated types reflect actual field names, casing, and nesting instead of a guess.
- Iterating on Zod schemas: After generating a Zod schema, it is common to manually tighten specific fields afterward — for example replacing a generic string field with `.email()` or `.uuid()` once you know the semantic meaning of that field.
- Go and Rust struct naming: Both generators convert JSON keys to the idiomatic casing for that language (PascalCase for Go, snake_case for Rust) while preserving the original key via a struct tag, so serialization still round-trips correctly.
- Handling large nested payloads: For deeply nested JSON, generate one target type at a time and copy each nested interface or struct separately into your codebase, which keeps large schemas easier to review during a pull request.
Frequently Asked Questions
Is my data safe?
Absolutely. This tool runs entirely in your browser using JavaScript. We do not store, record, or transmit your JSON data to any server.
How does it handle mixed arrays?
For mixed arrays (e.g., strings and numbers), the tool attempts to create a union type or falls back to `any` (or `interface{ }`) to ensure valid code generation.
Can I use this for API responses?
Yes! This is the primary use case. Simply copy the JSON response from Postman or your browser's network tab, paste it here, and generate the corresponding Interface or Struct to use in your application.
What is Zod?
Zod is a TypeScript-first schema declaration and validation library. While TypeScript interfaces only exist at compile time, Zod schemas allow you to validate data at runtime, which is crucial for handling external API data safely.
Why are Rust structs using Serde?
Serde is the standard serialization framework for Rust. We automatically add `#[derive(Serialize, Deserialize)]` and `#[serde(rename_all = "camelCase")]` attributes to make the structs ready for real-world usage.
Does it detect optional or nullable fields?
Yes. If a field is missing in some parts of your sample JSON or explicitly set to `null`, the tool marks it as optional (e.g., `field?: string` in TypeScript, `Option<String>` in Rust, or `*string` in Go) rather than assuming it is always present.