Generate a TypeScript interface from a JSON object instantly.
About this tool
Paste a JSON object or array to generate a matching TypeScript interface. Arrays are sampled from their first element; a mixed-type array produces a union type; an empty array produces unknown[]. This is a best-effort heuristic, not a full schema inference engine — always review the generated types before committing them.
Paste a JSON object and Tabreon generates a matching TypeScript interface instantly — nested objects, arrays, and unions included — entirely in your browser.
Why use Tabreon for this?
Type inference runs client-side — the JSON you paste, which may be a real API response, is never sent to a server.
Handles nested objects, sampled array element types, and mixed-type unions rather than falling back to `any`.
Instant generation with no account or request limit.
How to convert JSON to a TypeScript interface
1Paste your JSON. Paste a JSON object or array into the input panel.
2Click Generate Interface. A TypeScript `interface Root { ... }` (or `type Root = ...` for a top-level array) appears in the output panel.
3Copy the result. Copy the generated interface into your codebase, renaming `Root` to whatever fits your context.
What is JSON to TypeScript conversion?
When working with an API response or config file, writing the matching TypeScript types by hand is repetitive and error-prone. This tool inspects a JSON value's shape — object keys, array element types, primitive types — and generates a best-effort TypeScript interface describing that shape, saving the manual transcription step.
How Tabreon handles your data
Inference runs entirely in your browser's JavaScript engine — the JSON you paste is never transmitted to a server.
Key features
Nested object support with correctly indented sub-interfaces
Array element types sampled from the first element
Union types for arrays containing mixed primitive types
`unknown[]` for empty arrays, avoiding an incorrect type guess
Common use cases
Generating a starting interface for a new API response before writing a data-fetching hook
Quickly checking a nested JSON payload's shape while debugging a type error
Bootstrapping types for a JSON config file used in a TypeScript project
Common mistakes & limitations
This is a heuristic based on one sample value, not a full JSON Schema — array types are inferred from the first element only, so a differently-shaped second element is not detected.
Optional fields, string literal unions, and enums are not inferred; every field is generated as required with a general primitive type.
Frequently asked questions
No. Type inference happens locally in your browser — your JSON is never transmitted to a server.
Array types are inferred from the first element only, as a fast heuristic. If later elements have a different shape, manually widen the generated type after reviewing the full dataset.
The tool always names the top-level type `Root` — copy the output and rename it to whatever fits your codebase before using it.