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Install guidePaste JSON and instantly generate TypeScript interfaces.
Generate TypeScript interfaces from JSON samples to accelerate typed integration work, reduce manual modeling errors, and improve API contract clarity.
It infers object and array shapes from JSON input and emits TypeScript definitions suitable for frontend, backend, and shared SDK workflows.
It gives teams a fast baseline for typed payload contracts, especially during early API exploration or third-party integration spikes.
It supports iterative schema refinement by letting you adjust source samples and quickly compare generated model differences.
API response sample
{"id":1,"name":"A1","tags":["p1"],"active":true}Nested payload
{"order":{"id":"A-42","items":[{"sku":"x","qty":2}]}}Array root
[{"slug":"svc-42","stars":42}]Interface output
export interface User {
id: number;
name: string;
tags: string[];
active: boolean;
}Nested interface output
export interface Order {
id: string;
items: OrderItems[];
}Array type output
export type ProjectList = Project[];
Generated type too broad
Use representative samples and include edge-case payloads before finalizing interfaces.
Optional vs required confusion
Confirm whether missing fields are truly optional in production data, then adjust model flags.
Union-like payloads collapse poorly
Split samples by variant and model discriminated unions manually where needed.
Runtime assumptions not enforced
Pair generated interfaces with runtime validation when handling untrusted external input.
JSON → TypeScript should be treated as a repeatable validation step before merge, release, and handoff.
Can this replace schema-driven codegen?
It is best for rapid prototyping; schema-first pipelines remain better for strict, long-term contract governance.
Why do I still need runtime validation?
TypeScript checks compile-time assumptions only; runtime payloads can still violate expected shapes.
How do I improve inferred model quality?
Feed realistic samples, include boundary cases, and review generated output against API docs.
Should I commit generated interfaces directly?
Yes after review; keep them under tests and align naming conventions with your codebase standards.