Mock API Generator Online – AI-Assisted Smart Responses

Our Mock API Generator helps developers quickly create realistic API endpoints for testing and development. With AI-assisted smart generation, you can describe your API in plain English and automatically generate mock responses, latency, error scenarios, and dynamic JSON data all directly in your browser.

Endpoint Configuration

Endpoint Setup
Simulation Options
0ms
0%
IP Restriction (Optional)

Response Body Template

🎲 Template Variables (Click to Insert)

{{uuid}}+
{{firstName}}+
{{lastName}}+
{{fullName}}+
{{email}}+
{{phone}}+
{{avatar}}+
{{username}}+
{{company}}+
{{jobTitle}}+
{{street}}+
{{city}}+
{{country}}+
{{zipCode}}+
{{isoDate}}+
{{date}}+
{{datetime}}+
{{time}}+
{{boolean}}+
{{number:N}}+
{{number:min,max}}+
{{float:min,max}}+
{{percentage}}+
{{oneOf:...}}+
{{id}}+
{{slug}}+
{{url}}+
{{sentence}}+
{{paragraph}}+
{{lorem:N}}+
{{color}}+
{{price}}+
{{creditCard}}+
{{ipAddress}}+
{{macAddress}}+
{{imageUrl}}+
➕ Add Custom Variable
Enter a single value for this variable

📡 Generated Endpoint

GET https://api.mockendpoint.dev/api/users

Generated Response

📜 Request History

No requests yet. Generate and test an endpoint to see history.

💾 My Saved Endpoints

Loading your saved endpoints...

Free Alternative to JSONPlaceholder, Mocky.io, Beeceptor & MockAPI.io

Feature Our Tool JSONPlaceholder Mocky.io Beeceptor MockAPI.io
Custom JSON Responses ✅ ❌ ✅ ✅ ✅
Dynamic Template Variables ✅ ❌ ❌ ⚠️ ✅
Latency Simulation ✅ ❌ ⚠️ ✅ ⚠️
Error Rate Simulation ✅ ❌ ❌ ✅ ❌
IP Restriction Security ✅ ❌ ❌ ❌ ❌
OpenAPI/Swagger Export ✅ ❌ ❌ ❌ ❌
No Signup Required ✅ ✅ ✅ ⚠️ ❌
AI-Assisted Generation ✅ ❌ ❌ ❌ ❌

Mock API Features for Frontend Development

What is Mock API Generator?

A Mock API Generator creates simulated REST API endpoints that return fake but realistic data. It's essential for frontend developers who need to build and test applications before the real backend is ready. Our generator supports template variables, custom responses, and advanced simulation features.

Related tools: For simpler use cases, try our Dummy JSON API for ready-to-use endpoints, or the Dummy JSON Generator for a UI-based data generator.

✨ Key Features

  • AI-Assisted Generation - Describe your API in plain English and generate mock responses automatically
  • Smart Template Variables - Use {{firstName}}, {{email}} for realistic dynamic data
  • Intelligent Latency & Error Simulation - Test loading states and error handling with configurable rates
  • Multiple HTTP Methods - Full support for GET, POST, PUT, DELETE operations
  • OpenAPI Export - Generate Swagger documentation automatically

Common Use Cases

  • Frontend development without backend
  • UI/UX prototyping with realistic data
  • Testing error handling and edge cases
  • Demo applications and presentations
  • API design and documentation
  • Load testing and performance testing

Template Variable Examples

{{uuid}} → "a1b2c3d4-e5f6-..."
{{firstName}} → "John"
{{email}} → "john.doe@example.com"
{{number:100}} → Random 0-100
{{lorem:20}} → 20 words of lorem ipsum
{{isoDate}} → "2024-01-15T10:30:00Z"

IP Restriction

  • Enable IP Restriction to limit access to specific IPs
  • Your public IP is auto-detected on page load
  • Click "Add My IP" to whitelist your current IP
  • Non-whitelisted IPs get 403 Forbidden
  • Perfect for secure API testing

🔐 Server Endpoints

Click "Create Server Endpoint" to generate a real API URL that persists on our server. Share this URL with your team or use it in your app. Server endpoints support:

  • IP restriction for security
  • Latency simulation
  • Error rate simulation
  • Template variables

Complete Guide

Learn everything about using the Mock API Generator with our comprehensive guide:

  • Step-by-step tutorials
  • Template variable reference
  • Response examples
  • IP restriction best practices
Read the Guide →

Frequently Asked Questions

What is a Mock API Generator? +
Is this tool completely free to use? +
How does IP restriction work? +
How do I generate multiple records? +
Can I see my saved endpoints after refreshing the page? +
What are template variables? +
Does this Mock API Generator use AI? +
Can I use this tool without AI? +
How do I test latency and error handling? +

📋 Quick Start Templates

Copy these templates to quickly create common API responses:

👤 User API Response

{
  "id": "{{uuid}}",
  "name": "{{firstName}} {{lastName}}",
  "email": "{{email}}",
  "avatar": "{{avatar}}",
  "createdAt": "{{isoDate}}"
}

🛍️ Product API Response

{
  "id": "{{uuid}}",
  "name": "{{product}}",
  "price": {{number:999}},
  "inStock": {{boolean}},
  "category": "{{category}}"
}

📝 Blog Post API Response

{
  "id": "{{uuid}}",
  "title": "{{sentence:6}}",
  "excerpt": "{{lorem:20}}",
  "author": "{{firstName}} {{lastName}}",
  "publishedAt": "{{isoDate}}"
}

🔐 Auth API Response

{
  "token": "{{uuid}}-{{uuid}}",
  "user": {
    "id": "{{uuid}}",
    "email": "{{email}}",
    "role": "admin"
  },
  "expiresIn": 3600
}

🔧 Related Developer Tools

🎲

Dummy JSON Generator

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🔄

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📋

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✨

JSON Formatter

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🔔

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🧪

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🔗

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