Generate Mock Data (Free Online Tool)

Generate mock JSON data from a template for testing, demos, or seeding pipelines

Paste your JSON → Get results instantly (no signup)

⚡ Instant resultsNo signupRuns in your browser

Try examples:

→ Generate mock user records from this example object.

Output✓

{
  "id": 1,
  "name": "John Doe",
  "email": "john@example.com",
  "age": 30
}

Output✓

1[
2  {
3    "id": "a1b2c3d4-e5f6-7890-abcd-ef1234567890",
4    "name": "Jane Smith",
5    "email": "jane.smith@example.com",
6    "age": 42
7  },
8  {
9    "id": "b2c3d4e5-f6a7-8901-bcde-f12345678901",
10    "name": "Bob Wilson",
11    "email": "bob.wilson@example.net",
12    "age": 28
13  },
14  {
15    "id": "c3d4e5f6-a7b8-9012-cdef-123456789012",
16    "name": "Alice Johnson",
17    "email": "alice.johnson@example.org",
18    "age": 55
19  }
20]

Love the result?

Use this exact pipeline in your app, backend, or LLM workflow.

No setup needed. Works with curl, Node, Python.

Uses example data. For edited input, copy from the playground.

Read integration guide

Works with:

API responses
Nested JSON
Arrays & objects

Example: input → output

Input / OutputInputOutput

Input

{
  "id": 1,
  "name": "John Doe",
  "email": "john@example.com",
  "age": 30
}

Output

[
  {
    "id": "a1b2c3d4-e5f6-7890-abcd-ef1234567890",
    "name": "Jane Smith",
    "email": "jane.smith@example.com",
    "age": 42
  },
  {
    "id": "b2c3d4e5-f6a7-8901-bcde-f12345678901",
    "name": "Bob Wilson",
    "email": "bob.wilson@example.net",
    "age": 28
  },
  {
    "id": "c3d4e5f6-a7b8-9012-cdef-123456789012",
    "name": "Alice Johnson",
    "email": "alice.johnson@example.org",
    "age": 55
  }
]

Advanced usage (optional)

Generate Mock Data

v1.0.0

Generate

objectarraydestructive

Description

Generate Mock Data

Generate realistic mock data from a JSON template with smart field detection. Provide a sample object and the utility produces multiple records with randomized but realistic values based on field names and types.

How It Works

Provide a template: Input a JSON object representing the desired structure
Configure field types: Each field is auto-detected based on its name (e.g., email → email type, name → full name type). You can override any detection.
Set record count: Choose how many records to generate (1–10,000)
Generate: The utility produces an array of objects matching your template structure

Supported Mock Types

Category	Types
Identifiers	uuid, runningNumber, runningLetter
Person	firstName, lastName, fullName, username, age, jobTitle, avatarUrl
Contact	email, phone, password
Location	address, city, state, zipCode, country, countryCode, coordinate
Business	company, amount, currencyCode
Finance	creditCardNumber, creditCardCVV, creditCardExpiry, iban, bic
Web	url, domain, ipv4, ipv6, color, imageUrl
Date/Time	date, dateTime, pastDate, futureDate, timestamp
Text	loremSentence, loremParagraph
Primitives	string, number, boolean
Special	constant, totalCount

Configuration

Field	Type	Default	Description
Number of Records	number	`10`	How many records to generate (1–10,000)
Field Types	mock-type-tree	(required)	Configure mock data type for each field. Types are auto-detected from field names.

Use Cases

Development & Testing

Seed databases: Generate test data for development environments
API mocking: Create realistic response data for frontend development
Load testing: Generate large datasets for performance testing

Prototyping

UI mockups: Generate sample data for UI component development
Demo data: Create realistic-looking data for product demonstrations
Schema validation: Test data processing pipelines with varied inputs

Data Privacy

Test data replacement: Replace production data with realistic mock data
Anonymization: Generate fake records that maintain the same structure as real data

Configuration

Name	Type	Default	Description
Number of Records	`number`	`10`	How many records to generate (1-10,000)
Field Types	`mock-type-tree`	(required)	Configure mock data type for each field. Types are auto-detected from field names.

Examples

AI Prompt

Generate mock user records from this example object.

Output✓

{
  "id": 1,
  "name": "John Doe",
  "email": "john@example.com",
  "age": 30
}

Output✓

1[
2  {
3    "id": "a1b2c3d4-e5f6-7890-abcd-ef1234567890",
4    "name": "Jane Smith",
5    "email": "jane.smith@example.com",
6    "age": 42
7  },
8  {
9    "id": "b2c3d4e5-f6a7-8901-bcde-f12345678901",
10    "name": "Bob Wilson",
11    "email": "bob.wilson@example.net",
12    "age": 28
13  },
14  {
15    "id": "c3d4e5f6-a7b8-9012-cdef-123456789012",
16    "name": "Alice Johnson",
17    "email": "alice.johnson@example.org",
18    "age": 55
19  }
20]

Config

Number of Records

Field Types

1[
2  {
3    "path": "$.id",
4    "key": "id",
5    "mockType": "uuid"
6  },
7  {
8    "path": "$.name",
9    "key": "name",
10    "mockType": "fullName"
11  },
12  {
13    "path": "$.email",
14    "key": "email",
15    "mockType": "email"
16  },
17  {
18    "path": "$.age",
19    "key": "age",
20    "mockType": "age"
21  }
22]

API Usage

POST /api/v1/utilities/generate.mock-data

Example:

curl -X POST https://your-domain.com/api/v1/utilities/generate.mock-data \
  -H "Authorization: Bearer YOUR_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{"inputs":{"primary":{"id":1,"name":"John Doe","email":"john@example.com","age":30}},"config":{"recordCount":3,"fieldMappings":[{"path":"$.id","key":"id","mockType":"uuid"},{"path":"$.name","key":"name","mockType":"fullName"},{"path":"$.email","key":"email","mockType":"email"},{"path":"$.age","key":"age","mockType":"age"}]}}'

Response

1[
2  {
3    "id": "a1b2c3d4-e5f6-7890-abcd-ef1234567890",
4    "name": "Jane Smith",
5    "email": "jane.smith@example.com",
6    "age": 42
7  },
8  {
9    "id": "b2c3d4e5-f6a7-8901-bcde-f12345678901",
10    "name": "Bob Wilson",
11    "email": "bob.wilson@example.net",
12    "age": 28
13  },
14  {
15    "id": "c3d4e5f6-a7b8-9012-cdef-123456789012",
16    "name": "Alice Johnson",
17    "email": "alice.johnson@example.org",
18    "age": 55
19  }
20]