JSON Schema Generator
Generate a JSON Schema (draft 2020-12) from any JSON sample — types and required fields inferred automatically.
{
"id": 42,
"name": "Ada Lovelace",
"active": true,
"roles": ["admin", "editor"]
}Runs entirely in your browser — nothing is uploaded.
Generate a JSON Schema from JSON
Paste a representative JSON sample and this JSON Schema generator infers a schema (draft 2020-12): the correct type for each field (string, integer, number, boolean, object, array, null), nested schemas for objects and array items, and a required list of the keys present in your sample.
Why generate a schema?
A schema lets you validate incoming data, document an API contract, and catch shape changes before they reach production. Pair it with the repair brand: repair the JSON, then lock down its shape. The generated schema works with standard validators such as Ajv.
Works on messy JSON
Broken or AI-generated JSON is repaired first, so you can generate a schema even from imperfect samples. Need TypeScript types instead? Use the JSON to TypeScript tool, or open the full JSON Studio.
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