Mock API Response Builder

Create realistic HTTP responses for frontend demos, API documentation, QA scenarios, and local mocking. Pick a status code, add headers, shape the JSON payload, simulate latency, and instantly copy snippets for Express, Next.js, frontend mocks, or raw HTTP.

Status codes Headers JSON payload Latency simulation Code snippets

Response builder

Define the mock response once. Everything on the right updates from the same model.

Headers0
Body bytes0
JSON fields0
Latency0 ms
200 OK
This mock response is ready for frontend demos and local dev stubs.
Tip: Use this for polished example responses. For error scenarios, include fields like error, message, code, and details so frontend states are easier to test.

Generated output

Switch between raw HTTP, Express, Next.js, frontend fetch mock, and preview JSON.


        
Edit the response on the left and the snippets will stay synchronized.

      

    


    

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