Question 1

What is JSON Schema?

Accepted Answer

JSON Schema is a specification for defining structure and validation rules for JSON data. Describes expected types, required fields, formats, constraints. Used for API validation, configuration validation, documentation. Standard format: {"type": "object", "properties": {...}, "required": [...]}. Validates JSON against schema rules.

Question 2

How do I generate JSON Schema from JSON?

Accepted Answer

Paste JSON into generator tool. Tool analyzes JSON structure. Infers types from values: string, number, integer, boolean, array, object. Detects formats: email, URI, date-time from patterns. Outputs JSON Schema definition. Copy schema for use in APIs, validation. Manual: define types and properties matching your data.

Question 3

How do I validate JSON against a schema?

Accepted Answer

Use JSON Schema validators: Ajv (JavaScript), jsonschema (Python), JSON.NET (C#). Install library. Load schema and data. Call validate function. Returns true if valid, errors if invalid. Browser: use Ajv in frontend. Server: validate API requests before processing. CLI tools: ajv-cli for batch validation.

Question 4

What JSON Schema types are available?

Accepted Answer

Primitive types: string, number, integer, boolean, null. Compound types: array (items schema), object (properties schema). String formats: email, uri, date-time, uuid. Number constraints: minimum, maximum, multipleOf. Array constraints: minItems, maxItems, uniqueItems. Object constraints: required, additionalProperties.

Question 5

How do I use JSON Schema in OpenAPI/Swagger?

Accepted Answer

OpenAPI uses JSON Schema for request/response bodies. Define schema in components/schemas section. Reference with $ref: '#/components/schemas/SchemaName'. Use in paths for requestBody and responses. OpenAPI extends JSON Schema with nullable, discriminator. Generate schemas from sample data. Validate API payloads against schemas.

JSON Schema Generator

Input JSON

Generated JSON Schema

JSON Schema Types

Use Cases