Free browser-based tool

JSON Schema Generator

Generate JSON Schema Draft 2020-12 or Draft 7 from objects and arrays with required-field intersection, nullable types, formats, and conflict reports.

Guide

Infer JSON Schema from objects and arrays without first-row bias

Required properties are determined by intersection: a property is required only when it appears in every sampled object at that level.

Observed type conflicts, nullability, arrays, nested objects, and common string formats are represented in Draft 2020-12 or Draft 7 output. The generated schema must still be reviewed against business requirements.

Common questions

JSON Schema Generator FAQ

Which JSON Schema drafts are available?

Draft 2020-12 and Draft 7 schema identifiers are supported.

How are required fields inferred?

A field becomes required only when it exists in every sampled object at the same location.

Can sample data prove every allowed value?

No. Sample inference can describe observed data but cannot discover unobserved valid values, complete enums, or business rules.

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