API Mock Data Generator
Generate structured, realistic mock data for API endpoint testing. Define fields with names and types — UUID, name, email, integer, enum, date, and more — set how many rows you need, and export as a JSON array, NDJSON, or CSV. All generation runs entirely in your browser with no data sent to any server.
How to Use API Mock Data Generator
How to Use the API Mock Data Generator
Step 1: Set Row Count and Format
Rows — Enter how many records to generate (1–500). Use the quick presets (5, 10, 25, 50) or type a custom value.
Output format — Choose how the data is structured:
- JSON Array — A single
[{...}, {...}]array, ideal for seeding databases or mocking REST responses. - NDJSON — Newline-delimited JSON, one object per line. Used by log pipelines, Elasticsearch bulk imports, and streaming APIs.
- CSV — Comma-separated values with a header row. Open in Excel, import into databases, or use with data analysis tools.
Step 2: Load an Example Schema (Optional)
Click one of the example schema buttons to pre-fill the field list with a realistic starting point:
- User — id, firstName, lastName, email, phone, role (enum), isActive, createdAt
- Product — id, name, category (enum), price, stock, rating, inStock, createdAt
- Order — orderId, customerId, status (enum), total, itemCount, city, country, createdAt
- Log Entry — id (increment), level (enum), service (enum), message (sentence), ipAddress, duration, timestamp
Step 3: Define Your Fields
Each field has a Name and a Type. Optionally configure type-specific options where shown.
Available field types:
ID & System
- UUID v4 — Standard UUID, e.g.
550e8400-e29b-41d4-a716-446655440000 - Auto Increment — Sequential integers. Options: start value (default 1)
- Boolean —
trueorfalse
Numbers
- Integer — Whole numbers. Options:
min,max(e.g.1,100) - Float — Decimal numbers. Options:
min,max(e.g.0,1) - Price — Two-decimal currency value. Options:
min,max(e.g.5,500)
Person
- First Name, Last Name, Full Name — Realistic English names
- Username — e.g.
johnsmith42 - Email — e.g.
john.smith@gmail.com - Phone Number — US format:
+1-555-123-4567
Location
- Street Address, City, Country, Zip Code
Business
- Company, Job Title
Internet
- URL — e.g.
https://alpha.io - IP Address — e.g.
192.168.1.42 - Hex Color — e.g.
#a3f2c1
Date & Time
- Date — ISO date string (YYYY-MM-DD). Options:
start,enddate range - Date + Time — ISO datetime string. Options:
start,enddate range - Unix Timestamp — Seconds since epoch
Text
- Random Word — NATO phonetic or common word
- Sentence — Random 6–12 word sentence
Custom
- Enum — Pick randomly from your list. Options: comma-separated values (e.g.
active,inactive,pending)
Step 4: Generate and Export
Click Generate N Records. The output appears instantly in the right panel.
- Copy — Copy all output to clipboard
- Download — Save as
.json,.ndjson, or.csvfile - Re-generate — Click Generate again to get a new random dataset with the same schema
Tips
- Field names support any string — use camelCase (
createdAt), snake_case (created_at), or any convention that matches your API - Use Enum for status fields, categories, or any fixed set of values
- Use Auto Increment for sequential IDs when you need predictable order
- Combine UUID for
idand dateTime forcreatedAtto match common REST API patterns
Frequently Asked Questions
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