Paste JSON and generate TypeScript interfaces locally for API responses, fixtures, and typed frontends.
Infer TypeScript from representative JSON.
export interface Tool {
id: string;
title: string;
status: string;
tags: Array<string>;
metrics: Metrics;
owner?: null;
}
export interface Metrics {
users: number;
conversion: number;
}Paste representative JSON payloads from APIs, logs, or fixtures.
Generate exportable TypeScript interfaces with nested object support.
Infers array item types and merges mixed primitive values into unions.
Quotes property names that are not valid TypeScript identifiers.
Move generated types straight into your editor.
Your API payload stays in the browser.
No. It is a quick interface inference tool for representative payloads. For strict contracts, pair it with JSON Schema or runtime validators.
Null properties are marked optional and typed as null in this first version.
No. Type generation runs locally.