json-schema-faker/json-schema-faker

Health v2 · maintenance only

Adoption not part of the score

3447 stars · 343 forks observed · 2026-10-19

What it is AI-extracted, prompt v1, taxonomy v1, 2026-08-29, confidence not recorded

A JavaScript library that generates valid, realistic fake JSON data from JSON Schema definitions, supporting JSON Schema 2019-09 and 2020-12. It offers seeded deterministic output, $ref resolution, custom formats and extensions, and a CLI, with zero production dependencies.

Use cases

• generate fake JSON data from a JSON schema
• create mock API responses for testing
• generate realistic test fixtures from schemas
• seeded deterministic JSON data generation
• mock JSON payloads for unit tests
• generate sample data matching a schema for demos

When to choose

• you need test or mock data that conforms to a JSON Schema
• you want deterministic, reproducible fake data via seeds
• you need $ref, composition keywords, or regex pattern support
• you want a zero-dependency library usable in Node.js, Bun, or browsers

When to avoid

• you need fake data without an existing JSON Schema
• you need locale-specific realistic data beyond faker/chance extensions
• you need non-JSON formats like CSV or XML

Facets

library · maturity active

data-generation mocking testing json developer-tools testing apis bun browser cli cross-platform json-schema fake-data test-data faker mock-data seeded-random nodejs

Member repositories

For agents

markdown · JSON · MCP: product_card(name="json-schema-faker/json-schema-faker")