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Mock Data Generator & API Simulator

An advanced, schema-based tool for developers and testers to generate high-quality, realistic mock data. It features an intuitive UI for building custom data schemas with dozens of available data types. Users can generate thousands of rows of data in JSON, CSV, or SQL formats, with a live preview for instant feedback. The ability to save and load schemas makes it a reusable and indispensable part of any development and testing workflow.

Schema Builder

Add fields to your schema

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Click the "+" button to add your first field

Generation Options

Number of Rows

Output Format

Load Schema

Data Preview

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About This Tool

A powerful, free online tool to generate realistic mock and dummy data. Build custom schemas, choose from dozens of data types, and export in JSON, CSV, or SQL formats.

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Looking for more power?

Try our Data-Forge Mock Data Generator for advanced features like:

Drag-and-drop field ordering
Customizable blank value percentage
A powerful formula system
Saving and loading schemas

Data Types Reference

Names: First Name, Last Name, Full Name

Contact: Email, Phone Number, Username

Location: Address, City, State, Country, ZIP Code

Business: Company Name, Job Title, Department

Identifiers: UUID, Row Number, ID

Numeric: Random Number, Random Float, Boolean

Date/Time: Date, Time, DateTime, Timestamp

Media: Avatar URL, Image URL, Lorem Pixel

Text: Words, Sentences, Paragraphs, Lorem Ipsum

Web: IP Address, User Agent, URL

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Knowledge Base Articles

Asynchronous API Patterns: Complete Guide to Resilient System Architecture Master asynchronous API architecture with comprehensive workflows, best practices, and real-world implementations. Learn to build resilient systems that gracefully handle traffic spikes and prevent cascading failures. Updated 11/3/2025 Developer & Programming Tools : Complete Toolbox Overview Comprehensive overview of developer & programming tools featuring tools like Mock Data Generator & API Simulator, Advanced Diff Checker & Text Comparison 2, JSON Hero Toolkit. Includes use cases, workflows, and guidance on choosing the right utility. Updated 11/3/2025 Developer & Programming Tools : Best Practices & Implementation Guide Actionable best practices for developer & programming tools, covering workflows, common pitfalls, and optimization tips using tools such as Mock Data Generator & API Simulator, Advanced Diff Checker & Text Comparison 2, JSON Hero Toolkit. Updated 11/3/2025 GraphQL Editor & Visual IDE: Comprehensive Development and Schema Exploration Guide Master GraphQL development with comprehensive workflows, best practices, and real-world applications. Learn to explore schemas visually, optimize queries, and streamline API integration workflows. Updated 11/3/2025