Mock JSON Data Generator

Generate mock JSON data with fake names, emails, UUIDs and dates for testing — free.

Fields

About

About the Mock JSON Data Generator

Generates fake JSON records — strings, numbers, booleans, emails, UUIDs, dates and names — from a simple field schema you define.

Developers use it to get realistic-looking sample data for a UI or API before real data exists, while QA engineers use it to quickly build a batch of test records with the right shape. It's one of many free developer tools on Toolapt, and like every tool here, it's free to use with no sign-up and no limit on how many times you run it.

Choose what to view about this tool

Guide

Using the Mock JSON Data Generator

  1. 1

    Step 1

    Set each field's name and type using the default rows, or click "+ Add field" for more.

  2. 2

    Step 2

    Set how many records to generate.

  3. 3

    Step 3

    Click "Generate" to produce the JSON array.

  4. 4

    Step 4

    Copy the result, or Clear to start over with a different schema.

  • Supports seven field types: String, Number, Boolean, Email, UUID, Date and Name
  • Generates up to 200 records in one go, each following your exact field schema
  • Uses the browser's cryptographic random number generator to build realistic UUIDs
  • Comes pre-filled with a common id/name/email schema so you can generate something useful immediately
  • Runs entirely in your browser — no data is ever uploaded to a server
  • Free to use, with no limit on how many times you run it
  • Fully responsive, so it works just as well on a phone as on a desktop

Developers

Developers use the Mock JSON Data Generator for populating a UI with realistic-looking sample records before the real API or database exists.

QA engineers

QA engineers use the Mock JSON Data Generator for quickly building a batch of test records with a known shape to feed into a test suite.

Frontend developers

Frontend developers use the Mock JSON Data Generator for prototyping a list or table component against data that looks like the real thing.

Students learning APIs

Students learning APIs use the Mock JSON Data Generator for getting sample JSON to practice parsing and displaying without needing a live backend.

Examples

Mock JSON Data Generator examples

4 worked examples

01

Default id/name/email schema

The pre-filled id/name/email schema set to 2 records generates a JSON array of 2 objects, each with an id, name and email field in that order.

02

A UUID field

Adding a field named "sessionId" with type UUID generates a value like "550e8400-e29b-41d4-a716-446655440000" for each record, built with the browser's cryptographic random generator.

03

Boolean and Number fields at maximum volume

Adding "active" (Boolean) and "score" (Number) fields and setting Records to 200 — the maximum allowed — generates 200 objects, each with true/false and numeric values.

04

A Date field

Adding a field named "signupDate" with type Date produces a standard ISO date string, such as "2024-03-17", for each generated record.

Related tools

Code Minifier

Minify JavaScript, CSS or HTML using the same real minifiers bundlers use — Terser, csso and html-minifier-terser.

Use it

URL Shortener

Turn a long link into a short one that redirects visitors to the original address.

Use it

Cron Expression Generator

Build a five-field cron expression from simple fields or presets, and see its next run times.

Use it

JWT Decoder

Read the header and payload of a JSON Web Token, including expiry times.

Use it

Regex Tester

Test a regular expression against sample text and inspect every match and group.

Use it

Cron Expression Parser

List the next run times for a five-field cron schedule, in UTC.

Use it

FAQ

Frequently asked questions

Quick answers to common questions about the Mock JSON Data Generator.

What does the Mock JSON Data Generator do?

It generates however many fake JSON records you ask for, following a schema of field names and types that you define.

Is the Mock JSON Data Generator free to use?

Yes. It's free, with no sign-up, no watermark and no limit on how many times you use it.

Is my schema safe when I use this tool?

Yes. Everything is generated entirely on your own device — nothing about your schema or the generated data is sent to a server.

Which field types are supported?

String, Number, Boolean, Email, UUID, Date and Name — enough to cover most everyday test-data schemas.

How many records can I generate at once?

Up to 200 records in a single click, which covers most prototyping and small-scale testing needs.

Is the generated data real information?

No. Every value — including names and emails — is randomly generated and fictional; it doesn't reference or resemble any real person's data.

Can I use the Mock JSON Data Generator on my phone?

Yes. The page is fully responsive and works on mobile, tablet and desktop browsers alike.

Does the Mock JSON Data Generator have any limitations?

It generates flat records with simple field types; it doesn't currently support nested objects, arrays, or relationships between fields.

Still have a question? Contact us

Report a problem

Mock JSON Data Generator

What went wrong?
    or paste a screenshot