About this tool
Mock Data Generator is a free, in-browser schema builder for realistic test datasets. Define any number of columns, give each a type — integer or decimal range, name, email, date range, boolean, UUID, city, pick-list, or lorem words — set a row count, and generate ready-to-use fake data. Everything is produced on your device, so nothing is uploaded.
Unlike a basic random CSV maker, this tool is schema-driven: you control each column's name, type, and options, then export the same dataset as CSV, a JSON array of typed objects, or SQL INSERT statements for a table you name. Random values use the browser's crypto randomness where possible for good variety.
Because it runs entirely locally it is a private, offline-friendly way to seed databases, populate demos, and test data pipelines without hand-writing rows or exposing anything to a server.
Frequently asked questions
How do the per-type options work?
Integer and decimal types read a range like 1-1000; date reads a start,end pair such as 2020-01-01,2025-12-31; pick reads a comma-separated list of choices; and lorem reads a word count. Types like name, email, uuid, and city need no options.
What do the CSV, JSON, and SQL outputs look like?
CSV has a header row plus one line per record with quoting where needed; JSON is a pretty-printed array of objects where numbers and booleans keep their native types; SQL is one INSERT statement per row into the table name you provide, with strings escaped and numbers left unquoted.
Is the data reproducible or unique?
Values are freshly randomised on each generate, so you get a new dataset every time. An integer column literally named id over the default range is auto-numbered 1..N so it reads like a primary key.
How many rows can I generate?
Up to 5000 rows per run to keep the page responsive; generate again or concatenate outputs if you need more, and remember the whole process stays in your browser.
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