Free API Response Mocker Online – No Login | Jaconir
A free tool for frontend developers to instantly create mock JSON API endpoints from a schema. Define your data structure, generate a shareable URL, and start building your UI without waiting for the backend.
Your endpoint URL will appear here.
Your generated JSON response will appear here.
Features
Schema-Driven Mocking
Generates realistic data based on JSON schema types and formats.
Instant Endpoint URL
Get a shareable, temporary API endpoint the moment you generate your data.
Client-Side & Secure
All data is encoded into the URL itself; nothing is stored on our servers.
- Define Your Schema: Write a JSON Schema that describes your desired API response. Use our example to get started.
- Generate Data & Endpoint: Click "Generate Data & Endpoint". This creates mock data and encodes it into a shareable, temporary URL.
- Copy & Use: Copy your generated endpoint URL and use it in your frontend application's `fetch` calls. It behaves just like a real read-only API endpoint.
Why Use This Tool?
Frontend First
Unblock your frontend team. Build and test your UI without waiting for the backend to be ready.
Rapid Prototyping
Quickly stand up a fake API to test new features or build interactive prototypes for user feedback.
Learning & Demos
Perfect for creating live demos, tutorials, or code examples that need to fetch data from an API.