Generate JSON Server configuration files from endpoint definitions. Set up a fully functional mock API server in seconds. Code never leaves your device — formatting and validation run locally in your browser.
Content reviewed October 2026 · About Toolzum
Generate realistic mock JSON from field specs — names, emails, dates, nested objects. Fill frontends before backends exist — local generation, free, no signup.
Generate secure API keys with configurable length, character set, and optional prefix. Use with any authentication scheme.
Generate Postman collection JSON from endpoint descriptions. Create ready-to-import collections with method and path for each endpoint.
Bidirectional YAML to JSON and JSON to YAML conversion with auto-format detection and real-time preview. Perfect for configuration files, API payloads, and data migration.
Generate type definitions from pasted JSON for TypeScript, Java, C#, Python, Go, Rust, and Kotlin (plus a TS interface flavor). Everything runs locally in your browser — nothing is uploaded.
It generates a db.json file and route configuration for JSON Server — a fake REST API. Define your endpoints and the tool outputs ready-to-use config files for instant mock server setup.
JSON Server is a Node.js tool that creates a full REST API from a JSON file. It supports GET, POST, PUT, PATCH, DELETE, filtering, pagination, and sorting — no backend code needed.
Yes. Define relationships like /posts/:id/comments by using nested object structures in the endpoint definitions. JSON Server handles the relational routing automatically.
The tool generates the config structure. For sample data, pair it with the Fake Data Generator or populate the db.json manually with realistic entries.
Install JSON Server (npm install -g json-server), then run json-server --watch db.json. The server starts on port 3000 with full CRUD endpoints.
API Mock Data Generator
Generate realistic mock JSON from field specs — names, emails, dates, nested objects. Fill frontends before backends exist — local generation, free, no signup.
Mock API Response Generator
Craft canned API responses with status codes, headers, and bodies for testing error paths. Simulate 404s and 500s without a server — local, free, no signup.