How does JSONBlitz generate TypeScript interfaces?

It recursively traverses the parsed JSON, infers types for each value, and generates a named interface with correct TypeScript syntax including optional fields for nullable values.

Does it handle arrays of objects?

Yes. An array like [{"id":1,"name":"Alice"}] generates both the item interface and the typed array. Nested arrays and mixed-type arrays are also handled.

Can I use the generated interface directly in my codebase?

Yes. Copy from the Types and Schemas tab and paste into your TypeScript file. The interface is ready to use with no modifications needed for standard JSON shapes.

Does it generate types for deeply nested JSON?

Yes. The generator recurses through all nesting levels. Each nested object becomes its own named interface, referenced by the parent.

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Stop writing TypeScript interfaces by hand. Paste any JSON response — from an API, a config file, or a database query — and JSONBlitz instantly generates a fully recursive TypeScript interface and a matching Zod validation schema. Nested objects, arrays, optional fields, and all value types are handled automatically.

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JSONBlitz is a free, 100% private, client-side JSON formatter, validator, and repair tool. Paste messy JSON, console logs, API responses, or stack traces — JSONBlitz finds the JSON, fixes it automatically, and gives you clean output plus TypeScript interfaces, Zod schemas, and Python TypedDict code. Nothing ever leaves your browser.

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Frequently Asked Questions

How does JSONBlitz generate TypeScript interfaces?: It recursively traverses the parsed JSON, infers types for each value (string, number, boolean, null, array, nested object), and generates a named interface with correct TypeScript syntax including optional fields for nullable values.
Does it handle arrays of objects?: Yes. An array like [{"id":1,"name":"Alice"}] generates both the item interface and the typed array. Nested arrays and mixed-type arrays are also handled.
Can I use the generated interface directly in my codebase?: Yes. Copy from the Types and Schemas tab and paste into your TypeScript file. The interface is ready to use with no modifications needed for standard JSON shapes.
Does it generate types for deeply nested JSON?: Yes. The generator recurses through all nesting levels. Each nested object becomes its own named interface, referenced by the parent.