How long does the mock server stay active?

Each mock server instance is stored in Redis and remains active for 1 hour after creation or last update.

Can I update my mock responses after creating the server?

Yes, simply re-run the tool using the same mockId to hot-update your endpoint definitions instantly.

Does the server support dynamic responses?

Yes, you can use template tags like {{params.id}}, {{body.username}}, or {{now}} within your response body to generate dynamic data.

Is there a limit to the number of endpoints I can define?

You can define multiple endpoints within a single JSON configuration to simulate a complete API service.

What happens after the 1-hour TTL expires?

The mock server and its data are automatically removed from Redis once the 1-hour TTL is reached.

API Mock Server | Online Free Tool

Examples

1. Mocking a User Profile Service

Frontend Developer

Background

The backend team is still building the user profile service, but the frontend needs to implement the user dashboard.

Problem

Need a live endpoint that returns user data based on a dynamic ID from the URL.

How to use

Input the endpoint definition with dynamic parameters and retrieve the mock URL.

{"name": "User Service", "basePath": "/api", "endpoints": [{"method": "GET", "path": "/users/:id", "status": 200, "dynamicResponse": true, "responseBody": {"id": "{{params.id}}", "name": "John Doe"}}]}

Outcome

A temporary URL is generated, allowing the frontend to fetch user data by calling /api/users/123.

2. Hot-Updating Mock Responses

Full-Stack Developer

Background

Testing how the UI handles different error states from a login endpoint.

Problem

Need to change the mock response from success to unauthorized without restarting the entire testing environment.

How to use

Re-run the tool with the existing mockId and a modified JSON definition.

{"name": "Auth Service", "basePath": "/api", "endpoints": [{"method": "POST", "path": "/login", "status": 401, "responseBody": {"error": "Invalid credentials"}}]}

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Examples

1. Mocking a User Profile Service

2. Hot-Updating Mock Responses

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