API Response Mocker
Define mock API endpoints with custom status codes, headers, delays, and JSON bodies. Test your frontend without a backend.
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About API Response Mocking
What is API mocking?
API mocking creates simulated endpoints that return predefined responses. This lets frontend developers build and test UIs without waiting for the backend API to be ready.
Is any data sent externally?
No. Everything runs in your browser. Mock endpoints, responses, and test requests are all processed locally — nothing leaves your machine.
Can I simulate errors?
Yes! Set any HTTP status code (400, 401, 404, 500, etc.) and add error response bodies. You can also add artificial delays to simulate slow networks.
What export formats are supported?
Export mock configurations as Fetch API, Axios, cURL commands, or MSW (Mock Service Worker) handlers for easy integration into your codebase.
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