# Mock REST API Guide

Create free, instant REST API endpoints with custom responses, status codes, and advanced features. No signup required.

## Getting Started

Creating a mock REST API endpoint takes less than 30 seconds. Follow these simple steps:

1.

#### Visit the Homepage

Go to [mockapi.dog](/content/en/index.html) and select the "REST API" tab.

2.

#### Choose HTTP Method

Select GET, POST, PUT, PATCH, or DELETE based on your needs.

3.

#### Write Your JSON Response

Enter the JSON data you want the endpoint to return. The editor validates JSON in real-time.

```json
{
     "id": 1,
     "name": "John Doe",
     "email": "john@example.com"
}
```

4.

#### Configure Delays and Error Simulation Settings (Optional)

Add delays, status codes, error rates, or custom headers if needed.

5.

#### Complete Verification & Save

Complete the Turnstile verification, then click "Save Mock Endpoint". Your endpoint URL is automatically copied!

`https://abc123.mockapi.dog/api/users`

#### Your endpoint is live immediately!

No deployment, no waiting. Start making requests right away from your app, tests, or tools like Postman and curl.

## Core Features

### HTTP Methods

Support for all standard HTTP methods to match your API design.

- `GET` - Retrieve data
- `POST` - Create resources
- `PUT` - Full update
- `PATCH` - Partial update
- `DELETE` - Remove resources

### Status Codes

Return any HTTP status code to test success, errors, and edge cases.

- 200 OK - Success
- 201 Created
- 400 Bad Request
- 401 Unauthorized
- 500 Server Error

### JSON Responses

Return any valid JSON structure - from simple objects to complex nested data.

- Objects and arrays
- Nested structures
- Arrays of objects
- Real-time validation
- Proper Content-Type

## Advanced Features

Fine-tune your mock endpoints with powerful features for realistic testing scenarios.

### Response Delays

Simulate slow networks or server processing time by adding delays to responses.

Use Cases:

- Test loading states in UI
- Simulate slow 3G/4G networks
- Verify timeout handling
- Check skeleton screens

Example Delays:

500 ms - Fast 
2000 ms - Normal 
5000 ms - Slow

### Error Simulation

Set a percentage of requests to return errors. Perfect for testing error handling and retry logic.

Use Cases:

- Test error boundaries
- Verify retry mechanisms
- Check error messages
- Validate fallback UI

Error Rate Examples:

10% errors 
50% errors 
100% errors

### Conditional Errors

Return errors based on specific conditions like header values or request patterns.

Example Use Cases:

- Missing Header: Return 401 if X-API-Key header is not present
- Specific ID: Return 404 for userId "999" to test not found scenarios
- Request Method: Return 405 for unsupported HTTP methods

### TTL (Time to Live)

Set an expiration time for your endpoints. They automatically get deleted after the specified duration.

Available Options:

1 hour 
24 hours 
7 days 
30 days

Perfect for temporary tests or demos. No need to manually clean up.

## Common Tasks

### Create an Endpoint

1. Click "Create REST Endpoint" button  
2. Select HTTP method  
3. Enter your JSON response  
4. Configure optional settings  
5. Click "Create Endpoint"

✓ Your endpoint is now live!

### Edit an Endpoint

1. Find your endpoint in "My Endpoints" list  
2. Click the "Edit" button  
3. Modify response, status, or settings  
4. Save changes

✓ Changes are live immediately

### Delete an Endpoint

1. Locate the endpoint you want to remove  
2. Click the "Delete" button  
3. Confirm deletion

This action cannot be undone

### Test an Endpoint

Using curl:

`curl https://abc123.mockapi.dog/api/users`

Using JavaScript:

`fetch('https://abc123.mockapi.dog/api/users')`

## Troubleshooting

#### Endpoint returns 404 Not Found

**Solution:** Double-check the endpoint URL. Make sure you're using the exact URL provided after creation, including the unique ID.

#### Invalid JSON error when creating endpoint

**Solution:** Validate your JSON using the built-in editor. Common issues: missing commas, unquoted keys, trailing commas, or unescaped quotes.

#### CORS errors in browser

**Solution:** All endpoints automatically include CORS headers. If you still see errors, check if you're using the correct URL and HTTP method.

#### Endpoint is too slow

**Solution:** Check if you've added a response delay in advanced settings. Remove or reduce the delay value if not needed.

## Tips & Best Practices

#### Use Realistic Data

Include realistic field names, data types, and structures that match your real API. This makes testing more valuable.

#### Test Edge Cases

Create endpoints for empty arrays, null values, and error scenarios. This helps catch bugs early.

#### Document Your Endpoints

Keep a list of your endpoints and their purposes. Share URLs with team members for collaboration.

#### Use Delays Strategically

Add small delays to test loading states. Use longer delays to verify timeout handling.

#### Version Your Responses

Create multiple endpoints for different API versions. This helps test backward compatibility.

#### Clean Up Unused Endpoints

Regularly delete endpoints you no longer need. Use TTL to auto-expire temporary endpoints.

## Glossary

#### REST API

Representational State Transfer API - an architectural style for building web services using standard HTTP methods.

#### HTTP Methods

Standard request methods (GET, POST, PUT, PATCH, DELETE) that indicate the desired action for a resource.

#### Status Code

Three-digit code returned by server indicating the result of a request (200 OK, 404 Not Found, 500 Error, etc).

#### JSON

JavaScript Object Notation - a lightweight data format for structuring and exchanging data between client and server.

#### Endpoint

A specific URL where an API can be accessed. Each endpoint performs a specific function.

#### Mock API

A simulated API that returns predefined responses, used for testing and development without a real backend.

#### CORS

Cross-Origin Resource Sharing - a security feature that controls which domains can access your API from browsers.

#### TTL

Time To Live - the duration an endpoint exists before automatic deletion. Useful for temporary tests.

#### Error Rate

The percentage of requests that should return errors. Used to test error handling and retry logic.

#### Response Delay

Artificial wait time added before sending a response. Simulates slow networks or processing.

### Ready to Create Your First REST API?

Start building free mock REST API endpoints in seconds. No signup required, no credit card needed. Perfect for testing, prototyping, and development.